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Understanding Scoring Through Examples

The built-in scoring mechanism in Elasticsearch and Solr can seem mysterious to beginners and experienced practitioners alike. Instead of delving into the mathematical definitions of TF-IDF and BM25, this article will help you develop an intuitive understanding of these metrics by walking you through a series of simple examples. Each example consists of a query and list of several indexed documents. As you read along, try to guess which document comes up on top for each query. In each case, we will examine why that particular document gets the highest score and we’ll extract the general principle behind this behavior. A set of six examples will be followed by an extra credit section focusing on more advanced topics. Along with illustrating all of the key behaviors of BM25, our examples will touch on some of the gotchas around scoring in cluster scenario, where shards and replicas come into play. This article aims to teach you, in a short time and without any math, everything you’ll ever need to know about scoring. Having a solid understanding of scoring will prepare you to better diagnose relevance problems and improve relevance in real-world applications.

Query 1: dog

Let’s say I search for “dog” and there are only three documents in my index, as shown below. Which one of these documents is going to come up on top?

Doc 1: "dog"

Doc 2: "dog dog"

Doc 3: "dog dog dog

If you’re not quite sure, that’s good, because I haven’t given you enough of the context to know the answer. All the queries in this article were tested in Elasticsearch 7.4 where BM25 is the default scoring algorithm and its parameters are set as k=1.2 and b=0.7. (Please ignore that if it’s meaningless to you.) In most of the examples, we’ll assume the documents have a single text field called “title” that uses the standard analyzer:

"mappings": {
    "properties": {
      "title": {
        "type": "text",
        "analyzer": "standard"

For the most part, we’ll be doing simple match queries against the title field. Recall that the default boolean operator in Elasticsearch is OR. Here’s what our “dog” query looks like:

GET test/_search
  "query": {
      "match": {
          "title": "dog"

With those details out of the way, are you ready to tell me which one of those three documents (“dog,” “dog dog,” and “dog dog dog”) is going to get the highest score?

Here are the results:

ID Title Score
1 dog 0.167
2 dog dog 0.183
3 dog dog dog 0.189

Doc 3 gets the highest score because it has contains the highest number of tokens that match the query term. Another way to say this is that Doc 3 has the highest term frequency for the term in question. Of course if we were using the keyword analyzer, only Doc 1 would have matched the query, but we’re using the standard analyzer which breaks the title into multiple tokens. The moral of this story is that, from a scoring perspective at least,

High term frequency is good.

Before we move on, take a moment to compare Doc 1 and Doc 3. Notice that although Doc 3 has three times the term frequency for “dog” as Doc 1, its score isn’t three times as high. So while higher term frequency gives a higher score, its impact is not multiplicative.

Query 2: dog dog cat

Now I’m searching for “dog dog cat” and there are only two documents in my index:

Doc 1: "cat"
Doc 2: "dog"

Which one of these is going to come up on top? Or are they going to be tied?

In fact, “dog” is the winner here:

ID Title Score
1 cat 0.6
2 dog 1.3

Why does “dog” get twice the score of “cat?” The lesson here is that

Scores for each query term are summed.

Our query has two instances of “dog.” The score for the whole query is the sum of the scores for each term. Each instance of “dog” in our query is going to match the “dog” in Doc 2 and contribute roughly 0.6 to the score, for a total of 1.3. Using the standard analyzer, query terms aren’t deduplicated, so each instance of “dog” is treated separately. Doc 1 doesn’t get a similar advantage because our query only contains one instance of “cat.”

Query 3: dog dog cat

Now I’m executing the same query as before, “dog dog cat,” but my index is different. This time I have lots of “dog” documents:

Doc 1: "dog"
Doc 2: "dog"
Doc 3: "dog"
Doc 4: "dog"
Doc 5: "dog"
Doc 6: "dog"
Doc 7: "cat"

What’s going to happen now? Do the “dog” documents still win over “cat” because my query mentions “dog” twice? Here are the results:

ID Title Score
1 dog 0.4
2 dog 0.4
3 dog 0.4
4 dog 0.4
5 dog 0.4
6 dog 0.4
7 cat 1.5

The results are different this time because the terms have different document frequencies than before. A term’s document frequency is the number of documents in the index that contain the term. From a scoring perspective, low document frequency is good and high document frequency is bad. In this example, “cat” is a rare term in the index — it has low document frequency — so matches on that term help the score more than matches on “dog,” which is a common term. The lesson here is that:

Matches for rarer terms are better.

If I want to tell the search engine that a common term is particularly important to me in a certain scenario, I can boost the term. If I had executed my query with a boost of 7 on “dog,” the dog documents would come up above the cat document. Here’s how I’d set that up:

GET test/_search
 "query": {
  "query_string": {
   "query": "dog^7 cat",
   "fields": ["title"]

Query 4: dog cat

In this example I’m searching for “dog cat,” and I’ve got three documents in my index: one with a lot of dogs, one with a lot of cats, and one with a single instance of dog and cat each, plus a lot of mats.

Doc 1: "dog dog dog dog dog dog dog"
Doc 2: "cat cat cat cat cat cat cat"
Doc 3: "dog cat mat mat mat mat mat"

Which document comes up on top this time? Notice that in Doc 1 and Doc 2, every single term matches one of the query terms, whereas in Doc 3 there are five terms that don’t match anything. So the results might be a little surprising:

ID Title Score
1 dog dog dog dog dog dog dog 0.88
2 cat cat cat cat cat cat cat 0.88
3 dog cat mat mat mat mat mat 0.94

Document 3 gets the highest score because it has matches for both of the query terms, “dog” and “cat.” While Documents 1 and 2 have higher term frequency for “dog” and “cat” respectively, they each contain only one of the terms. The lesson is that

Matching more query terms is good.

Query 5: dog

Now I’ll search for “dog” and there are only two documents in my index:

Doc 1: "dog cat zebra"
Doc 2: "dog cat

Both of these documents match my query, and both have some terms that don’t match. Which document does the best? Here are there results:

ID Title Score
1 dog cat zebra 0.16
2 dog cat 0.19

In this case, Document 2 does better because it is shorter. The thinking is that when a term occurs in a shorter document, we can be more confident that the term is significant to the document (or that the document is about the term). When a term occurs in a longer document, we have less confidence that this occurrence is meaningful. The lesson here is that

Matches in shorter documents are better.

Query 6: orange dog

Now let’s consider a scenario that’s a little more complicated than the previous ones. For the first time, our documents will have two fields, “color” and “type.”

Doc 1: {"color": "brown", "type": "dog"}
Doc 2: {"color": "brown", "type": "dog"}
Doc 3: {"color": "brown", "type": "cat"}
Doc 4: {"color": "orange", "type": "cat"}

We’re searching for “orange dog” but as you can see, there are no orange dogs in the index. There are two brown dogs, a brown cat, and an orange cat. Which one is going to come up on top?

I should mention that we’re searching across both fields using a multi_match like this:

GET test/_search
  "query": {
   "multi_match": {
    "query": "orange dog", 
    "fields": ["type", "color"],
    "type": "most_fields"

Here are the results:

ID Color Type Score
1 brown dog 0.6
2 brown dog 0.6
3 brown cat N/A
4 orange cat 1.2

This example hints at some of the unexpected behavior that can arise when we search across multiple fields. The search engine doesn’t know which field is most important to us. If someone is searching for an orange dog, we might guess they’re more interested in seeing dogs than seeing arbitrary things that happen to be orange. (“Orange dog” would be very strange query to enter if you meant “show me anything that’s orange.”) In this case, however, the color field is taking priority because “orange” is a rare term within that field (there are 3 browns and only 1 orange). Within the type field, “dog” and “cat” have the same frequency. The orange cat comes up on top because a match for the rare term “orange” is treated as more valuable than a match for “dog.”

If we want to give more weight to the “type” field we can boost it like this:

GET test/_search
  "query": {
   "multi_match": {
    "query": "orange dog", 
    "fields": [“type^2", "color"],
    "type": "most_fields"

With the boost applied, the “brown dog” documents now score 1.3 and come up above the “orange cat.”

The lesson here is that searching across multiple fields can be tricky because the per-field scores are added together without concern for which fields are more important. To rectify this,

We can use boosting to express field priorities.

Query 7: dog

Now we’re moving into advanced territory although our query looks simpler than anything we’ve seen before. We’re searching for “dog” and our index has three identical “dog” documents:

Doc 1: "dog"
Doc 2: "dog"
Doc 3: "dog"

Which one is going to come up on top? You might guess that these three documents, being identical, should get the same score. So let’s take a moment to look at how ties are handled. When two documents have the same score, they’ll be sorted by their internal Lucene doc id. This internal id is different from the value in the document’s _id field, and it can differ even for the same document across replicas of a shard. If you really want ties to be broken in the same way regardless of which replica you hit, you can add a sort to your query, where you sort first by _score and then by a designated tiebreaker like _id or date.

But this point about tiebreaking is only an aside. When I actually ran this query, the documents didn’t come back with identical scores!

ID Title Score
1 dog 0.28
2 dog 0.18
3 dog 0.18

How is it possible that identical documents would get different scores? The lesson in this example is that

Term statistics are measured per shard.

Though I didn’t state it explicitly at the beginning of the post, all our previous examples were using one shard. In the current example, however, I set up my index with two shards. Document 1 landed on Shard 1 while Documents 2 and 3 landed on Shard 2. Document 1 got a higher score because within Shard 1, “dog” is a rarer term — it only occurs once. Within Shard 2, “dog” is more common — it occurs twice. Here’s how I set up the example:

PUT /test 
{ "settings": { "number_of_shards": 2 } }

PUT /test/_doc/1?routing=0
{ "title" : "dog" } 

PUT /test/_doc/2?routing=1
{ "title" : "dog" } 

PUT /test/_doc/3?routing=1
{ "title" : "dog" } 

If you’re working with multiple shards and you want scores to be consistent regardless of which shard a document lives in, you can do a Distributed Frequency Search by added the following parameter to your query: search_type=dfs_query_then_fetch. This tells Elasticsearch to retrieve term statistics from all the shards and combine them before computing the scores.

But its also important to know that

Replicas of a shard may have different term statistics.

This is a consequence of how deletion is handled in Lucene. Documents that are marked for deletion but not yet physically removed (when their segments are merged) still contribute to term statistics. When a document is deleted, all the replicas will immediately “know” about the deletion, but they might not carry it out physically at the same time, so they might end up with different term statistics. To reduce the impact of this, you can specify a user or session ID in the shard copy preference parameter. This encourages Elasticsearch to route requests from the same user to the same replicas, so that, for example, a user will not notice scoring discrepancies when issuing the same query multiple times.

Its also important to know that, from a scoring perspective,

Document updates behave like insertions, until segments are merged.

When you update a document in Lucene, a new version of it is written to disk and the old version is marked for deletion. But the old version continues to contribute to term statistics until it is physically deleted.

In the example below, I create a “dog cat” document and then I update its contents to be “dog zebra.” Immediately after the update, if I query for “dog” and look at the explain output, Elasticsearch tells me there are two documents containing the term “dog.” The number goes down to one after I do a _forcemerge. The moral: if you’re doing relevancy tuning in Elasticsearch, looking closely at scores, and also updating documents at the same time, be sure to run a _forcemerge after your updates, or else rebuild the index entirely.

PUT test/_doc/1
{ "title": "dog cat" }

GET test/_search?format=yaml
{ "query" : { "match" : { "title": "dog" } }, 
  "explain": true }

PUT test/_doc/1?refresh
{ "title": "dog zebra" }

GET test/_search?format=yaml
{ "query" : { "match" : { "title": "dog" } }, 
  "explain": true }

POST test/_forcemerge

GET test/_search?format=yaml
{ "query" : { "match" : { "title": "dog" } }, 
  “explain": true }

Query 8: dog cat

Now let’s take another look at Query 4, where we searched for “dog cat” and we found that a document containing both terms did better than documents with lots of instances of one term or the other. In Query 4, we were searching the title field, the only field available. Here, we’ve got two fields, pet1 and pet2:

Doc 1: {"pet1": "dog", "pet2": "dog"}
Doc 2: {"pet1": "dog", "pet2": "cat"}

We’ll do a multi_match including those two fields like this:

GET test/_search
  "query": {
   "multi_match": {
    "query": "dog cat", 
    "fields": [“pet1”, "pet2"],
    "type": "most_fields"

Since Document 2 matches both of our query terms we’d certainly hope that it does better than Document 1. That’s the lesson we took away from Query 4, right? Well, here are the results:

ID Pet 1 Pet 2 Score
1 dog dog 0.87
2 dog cat 0.87

You can see the documents are tied. It might look like “cat” is a rare term that should help Document 2 rise to the top, but within the Pet 2 field, “cat” and “dog” have the same document frequencies, and the scoring is done on a per-field basis. It also looks like Document 2 should get an advantage for matching more of the query terms, but again, the scoring is done a per-field basis: when we compute the score in the Pet 1 field, both documents do the same; when we compute the score in the Pet 2 field, both documents again do the same.

Does this contradict what we learned from Query 4? Not quite, but it warrants a refinement of the earlier lesson:

Matching more query terms within the same field is good. But there’s no advantage when the matches happen across fields.

If you’re not happy with this situation, there are some things you can do. You can combine the contents of Pet 1 and Pet 2 into a single field. You can also switch from the most_fields to the cross_fields query type to simulate a single field. (Just be aware that cross_fields has some other consequences on scoring, changing the procedure from field-centric to term-centric. We won’t go into details here.)

Query 9: orange dog

Now let’s revisit the lesson from Query 5, where we saw that matches in shorter fields are better. We’re going to search for “orange dog.” We have a “dog” document with a description mentioning that the dog is brown. And we have a “cat” document with a description mentioning that the cat is sometimes orange. Notice that the dog document has a longer description than the cat document, and both descriptions are longer than the contents of the type field.

Doc 1: {“type”: “dog”, “description”: “A sweet and loving pet that is always eager to play. Brown coat. Lorem ipsum dolor sit amet, consectetur adipiscing elit. Duis non nibh sagittis, mollis ex a, scelerisque nisl. Ut vitae pellentesque magna, ut tristique nisi. Maecenas ut urna a elit posuere scelerisque. Suspendisse vel urna turpis. Mauris viverra fermentum ullamcorper. Duis ac lacus nibh. Nulla auctor lacus in purus vulputate, maximus ultricies augue scelerisque.”}

Doc 2: {“type”: “cat”, “description”: “Puzzlingly grumpy. Occasionally turns orange.”}

We’ll do a multi_match like this:

GET test/_search
  "query": {
   "multi_match": {
    "query": "orange dog", 
    "fields": ["type", “description"],
    "type": "most_fields"

What’s going to take precedence here: the match for “dog” in the type field, which is a really short field, or the match for “orange” in the description field, which is significantly longer? If matches in shorter fields are better, shouldn’t “dog” win here? In fact, the results look like this:

ID Type Description Score
1 dog A sweet… brown… 0.69
2 cat Puzzlingly grumpy… orange. 1.06

The match for “orange” in the Description field is sending Document 2 to the top even though that match occurs in a longer field body than the match for “dog” in Document 1. Does this contradict what we learned about matches in short and long fields from Query 5? No, but it points to something we hadn’t mentioned. The lesson is that:

“Shortness” is relative to the field’s average.

Within the type field, “dog” and “cat” don’t get an advantage for being short because, in fact, they’re both of average length for that field. On the other hand, the description for the cat is shorter than average for the description field overall, so it gets a benefit for being “short.”

Query 10: abcd efghijklmnopqrstuvwxyz

Here’s an easy one to close out our set of examples. I’ve divided the alphabet into two query terms. One of them is a short term, “abcd,” and the other is a long term, “efghijklmnopqrstuvwxyz.” I’m going to search for both terms together: “abcd efghijklmnopqrstuvwxyz.” My index has one match for each term:

Doc 1: "abcd"
Doc 2: "efghijklmnopqrstuvwxyz"

Which document is going to do the best? The results look like this:

ID Title Score
1 abcd 0.69
2 efghijklmnopqrstuvwxyz 0.69

Why are the documents tied if it’s true that matches in shorter fields are better? The lesson is that

When we talk about a short or long field, we’re talking about how many terms the field contains, not how many characters. In this example, the titles for both documents are of length 1.

Term length is not significant.

That’s it for now. Hopefully these examples have helped build your intuitions about how scoring works in Elasticsearch and Solr. Thanks for following along! If you’d like to go further and understand how the BM25 scoring function actually achieves the behaviors we’ve seen here, check out our companion article on Understanding TF-IDF and BM25.

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  • With Service Providers: We may share Your personal information with Service Providers to monitor and analyze the use of our Service, to contact You.
  • For business transfers: We may share or transfer Your personal information in connection with, or during negotiations of, any merger, sale of Company assets, financing, or acquisition of all or a portion of Our business to another company.
  • With Affiliates: We may share Your information with Our affiliates, in which case we will require those affiliates to honor this Privacy Policy. Affiliates include Our parent company and any other subsidiaries, joint venture partners or other companies that We control or that are under common control with Us.
  • With business partners: We may share Your information with Our business partners to offer You certain products, services or promotions.
  • With other users: when You share personal information or otherwise interact in the public areas with other users, such information may be viewed by all users and may be publicly distributed outside.
  • With Your consent: We may disclose Your personal information for any other purpose with Your consent.


The Company will retain Your Personal Data only for as long as is necessary for the purposes set out in this Privacy Policy. We will retain and use Your Personal Data to the extent necessary to comply with our legal obligations (for example, if we are required to retain your data to comply with applicable laws), resolve disputes, and enforce our legal agreements and policies.

The Company will also retain Usage Data for internal analysis purposes. Usage Data is generally retained for a shorter period of time, except when this data is used to strengthen the security or to improve the functionality of Our Service, or We are legally obligated to retain this data for longer time periods.


Your information, including Personal Data, is processed at the Company’s operating offices and in any other places where the parties involved in the processing are located. It means that this information may be transferred to — and maintained on — computers located outside of Your state, province, country or other governmental jurisdiction where the data protection laws may differ than those from Your jurisdiction.

Your consent to this Privacy Policy followed by Your submission of such information represents Your agreement to that transfer.

The Company will take all steps reasonably necessary to ensure that Your data is treated securely and in accordance with this Privacy Policy and no transfer of Your Personal Data will take place to an organization or a country unless there are adequate controls in place including the security of Your data and other personal information.


You have the right to delete or request that We assist in deleting the Personal Data that We have collected about You.

Our Service may give You the ability to delete certain information about You from within the Service.

You may update, amend, or delete Your information at any time by signing in to Your Account, if you have one, and visiting the account settings section that allows you to manage Your personal information. You may also contact Us to request access to, correct, or delete any personal information that You have provided to Us.

Please note, however, that We may need to retain certain information when we have a legal obligation or lawful basis to do so.



If the Company is involved in a merger, acquisition or asset sale, Your Personal Data may be transferred. We will provide notice before Your Personal Data is transferred and becomes subject to a different Privacy Policy.


Under certain circumstances, the Company may be required to disclose Your Personal Data if required to do so by law or in response to valid requests by public authorities (e.g. a court or a government agency).


The Company may disclose Your Personal Data in the good faith belief that such action is necessary to:

  • Comply with a legal obligation
  • Protect and defend the rights or property of the Company
  • Prevent or investigate possible wrongdoing in connection with the Service
  • Protect the personal safety of Users of the Service or the public
  • Protect against legal liability


The security of Your Personal Data is important to Us, but remember that no method of transmission over the Internet, or method of electronic storage is 100% secure. While We strive to use commercially acceptable means to protect Your Personal Data, We cannot guarantee its absolute security.


The Service Providers We use may have access to Your Personal Data. These third-party vendors collect, store, use, process and transfer information about Your activity on Our Service in accordance with their Privacy Policies.


We may use third-party Service providers to monitor and analyze the use of our Service.

  • Google Analytics
    Google Analytics is a web analytics service offered by Google that tracks and reports website traffic. Google uses the data collected to track and monitor the use of our Service. This data is shared with other Google services. Google may use the collected data to contextualize and personalize the ads of its own advertising network.
    You can opt-out of having made your activity on the Service available to Google Analytics by installing the Google Analytics opt-out browser add-on. The add-on prevents the Google Analytics JavaScript (ga.js, analytics.js and dc.js) from sharing information with Google Analytics about visits activity.
    For more information on the privacy practices of Google, please visit the Google Privacy & Terms web page:



We may process Personal Data under the following conditions:

  • Consent: You have given Your consent for processing Personal Data for one or more specific purposes.
  • Performance of a contract: Provision of Personal Data is necessary for the performance of an agreement with You and/or for any pre-contractual obligations thereof.
  • Legal obligations: Processing Personal Data is necessary for compliance with a legal obligation to which the Company is subject.
  • Vital interests: Processing Personal Data is necessary in order to protect Your vital interests or of another natural person.
  • Public interests: Processing Personal Data is related to a task that is carried out in the public interest or in the exercise of official authority vested in the Company.
  • Legitimate interests: Processing Personal Data is necessary for the purposes of the legitimate interests pursued by the Company.

In any case, the Company will gladly help to clarify the specific legal basis that applies to the processing, and in particular whether the provision of Personal Data is a statutory or contractual requirement, or a requirement necessary to enter into a contract.


The Company undertakes to respect the confidentiality of Your Personal Data and to guarantee You can exercise Your rights.

You have the right under this Privacy Policy, and by law if You are within the EU, to:

  • Request access to Your Personal Data. The right to access, update or delete the information We have on You. Whenever made possible, you can access, update or request deletion of Your Personal Data directly within Your account settings section. If you are unable to perform these actions yourself, please contact Us to assist You. This also enables You to receive a copy of the Personal Data We hold about You.
  • Request correction of the Personal Data that We hold about You. You have the right to have any incomplete or inaccurate information We hold about You corrected.
  • Object to processing of Your Personal Data. This right exists where We are relying on a legitimate interest as the legal basis for Our processing and there is something about Your particular situation, which makes You want to object to our processing of Your Personal Data on this ground. You also have the right to object where We are processing Your Personal Data for direct marketing purposes.
  • Request erasure of Your Personal Data. You have the right to ask Us to delete or remove Personal Data when there is no good reason for Us to continue processing it.
  • Request the transfer of Your Personal Data. We will provide to You, or to a third-party You have chosen, Your Personal Data in a structured, commonly used, machine-readable format. Please note that this right only applies to automated information which You initially provided consent for Us to use or where We used the information to perform a contract with You.
  • Withdraw Your consent. You have the right to withdraw Your consent on using your Personal Data. If You withdraw Your consent, We may not be able to provide You with access to certain specific functionalities of the Service.


You may exercise Your rights of access, rectification, cancellation and opposition by contacting Us. Please note that we may ask You to verify Your identity before responding to such requests. If You make a request, We will try our best to respond to You as soon as possible.

You have the right to complain to a Data Protection Authority about Our collection and use of Your Personal Data. For more information, if You are in the European Economic Area (EEA), please contact Your local data protection authority in the EEA.


This privacy notice section for California residents supplements the information contained in Our Privacy Policy and it applies solely to all visitors, users, and others who reside in the State of California.


We collect information that identifies, relates to, describes, references, is capable of being associated with, or could reasonably be linked, directly or indirectly, with a particular Consumer or Device. The following is a list of categories of personal information which we may collect or may have been collected from California residents within the last twelve (12) months.

Please note that the categories and examples provided in the list below are those defined in the CCPA. This does not mean that all examples of that category of personal information were in fact collected by Us, but reflects our good faith belief to the best of our knowledge that some of that information from the applicable category may be and may have been collected. For example, certain categories of personal information would only be collected if You provided such personal information directly to Us.

  • Category A: Identifiers.
    Examples: A real name, alias, postal address, unique personal identifier, online identifier, Internet Protocol address, email address, account name, driver’s license number, passport number, or other similar identifiers.
    Collected: Yes.
  • Category B: Personal information categories listed in the California Customer Records statute (Cal. Civ. Code § 1798.80(e)).
    Examples: A name, signature, Social Security number, physical characteristics or description, address, telephone number, passport number, driver’s license or state identification card number, insurance policy number, education, employment, employment history, bank account number, credit card number, debit card number, or any other financial information, medical information, or health insurance information. Some personal information included in this category may overlap with other categories.
    Collected: Yes.
  • Category C: Protected classification characteristics under California or federal law.
    Examples: Age (40 years or older), race, color, ancestry, national origin, citizenship, religion or creed, marital status, medical condition, physical or mental disability, sex (including gender, gender identity, gender expression, pregnancy or childbirth and related medical conditions), sexual orientation, veteran or military status, genetic information (including familial genetic information).
    Collected: No.
  • Category D: Commercial information.
    Examples: Records and history of products or services purchased or considered.
    Collected: No.
  • Category E: Biometric information.
    Examples: Genetic, physiological, behavioral, and biological characteristics, or activity patterns used to extract a template or other identifier or identifying information, such as, fingerprints, faceprints, and voiceprints, iris or retina scans, keystroke, gait, or other physical patterns, and sleep, health, or exercise data.
    Collected: No.
  • Category F: Internet or other similar network activity.
    Examples: Interaction with our Service or advertisement.
    Collected: Yes.
  • Category G: Geolocation data.
    Examples: Approximate physical location.
    Collected: No.
  • Category H: Sensory data.
    Examples: Audio, electronic, visual, thermal, olfactory, or similar information.
    Collected: No.
  • Category I: Professional or employment-related information.
    Examples: Current or past job history or performance evaluations.
    Collected: No.
  • Category J: Non-public education information (per the Family Educational Rights and Privacy Act (20 U.S.C. Section 1232g, 34 C.F.R. Part 99)).
    Examples: Education records directly related to a student maintained by an educational institution or party acting on its behalf, such as grades, transcripts, class lists, student schedules, student identification codes, student financial information, or student disciplinary records.
    Collected: No.
  • Category K: Inferences drawn from other personal information.
    Examples: Profile reflecting a person’s preferences, characteristics, psychological trends, predispositions, behavior, attitudes, intelligence, abilities, and aptitudes.
    Collected: No.

Under CCPA, personal information does not include:

  • Publicly available information from government records
  • Deidentified or aggregated consumer information
  • Information excluded from the CCPA’s scope, such as:
    • Health or medical information covered by the Health Insurance Portability and Accountability Act of 1996 (HIPAA) and the California Confidentiality of Medical Information Act (CMIA) or clinical trial data
    • Personal Information covered by certain sector-specific privacy laws, including the Fair Credit Reporting Act (FRCA), the Gramm-Leach-Bliley Act (GLBA) or California Financial Information Privacy Act (FIPA), and the Driver’s Privacy Protection Act of 1994


We obtain the categories of personal information listed above from the following categories of sources:

  • Directly from You. For example, from the forms You complete on our Service, preferences You express or provide through our Service.
  • Indirectly from You. For example, from observing Your activity on our Service.
  • Automatically from You. For example, through cookies We or our Service Providers set on Your Device as You navigate through our Service.
  • From Service Providers. For example, third-party vendors to monitor and analyze the use of our Service, or other third-party vendors that We use to provide the Service to You.


We may use or disclose personal information We collect for “business purposes” or “commercial purposes” (as defined under the CCPA), which may include the following examples:

  • To operate our Service and provide You with our Service.
  • To provide You with support and to respond to Your inquiries, including to investigate and address Your concerns and monitor and improve our Service.
  • To fulfill or meet the reason You provided the information. For example, if You share Your contact information to ask a question about our Service, We will use that personal information to respond to Your inquiry.
  • To respond to law enforcement requests and as required by applicable law, court order, or governmental regulations.
  • As described to You when collecting Your personal information or as otherwise set forth in the CCPA.
  • For internal administrative and auditing purposes.
  • To detect security incidents and protect against malicious, deceptive, fraudulent or illegal activity, including, when necessary, to prosecute those responsible for such activities.

Please note that the examples provided above are illustrative and not intended to be exhaustive. For more details on how we use this information, please refer to the “Use of Your Personal Data” section.

If We decide to collect additional categories of personal information or use the personal information We collected for materially different, unrelated, or incompatible purposes We will update this Privacy Policy.


We may use or disclose and may have used or disclosed in the last twelve (12) months the following categories of personal information for business or commercial purposes:

  • Category A: Identifiers
  • Category B: Personal information categories listed in the California Customer Records statute (Cal. Civ. Code § 1798.80(e))
  • Category F: Internet or other similar network activity

Please note that the categories listed above are those defined in the CCPA. This does not mean that all examples of that category of personal information were in fact disclosed, but reflects our good faith belief to the best of our knowledge that some of that information from the applicable category may be and may have been disclosed.

When We disclose personal information for a business purpose or a commercial purpose, We enter a contract that describes the purpose and requires the recipient to both keep that personal information confidential and not use it for any purpose except performing the contract.


As defined in the CCPA, “sell” and “sale” mean selling, renting, releasing, disclosing, disseminating, making available, transferring, or otherwise communicating orally, in writing, or by electronic or other means, a consumer’s personal information by the business to a third party for valuable consideration. This means that We may have received some kind of benefit in return for sharing personal information, but not necessarily a monetary benefit.

Please note that the categories listed below are those defined in the CCPA. This does not mean that all examples of that category of personal information were in fact sold, but reflects our good faith belief to the best of our knowledge that some of that information from the applicable category may be and may have been shared for value in return.

We may sell and may have sold in the last twelve (12) months the following categories of personal information:

  • Category A: Identifiers
  • Category B: Personal information categories listed in the California Customer Records statute (Cal. Civ. Code § 1798.80(e))
  • Category F: Internet or other similar network activity


We may share Your personal information identified in the above categories with the following categories of third parties:

  • Service Providers
  • Our affiliates
  • Our business partners
  • Third party vendors to whom You or Your agents authorize Us to disclose Your personal information in connection with products or services We provide to You


We do not sell the personal information of Consumers We actually know are less than 16 years of age, unless We receive affirmative authorization (the “right to opt-in”) from either the Consumer who is between 13 and 16 years of age, or the parent or guardian of a Consumer less than 13 years of age. Consumers who opt-in to the sale of personal information may opt-out of future sales at any time. To exercise the right to opt-out, You (or Your authorized representative) may submit a request to Us by contacting Us.

If You have reason to believe that a child under the age of 13 (or 16) has provided Us with personal information, please contact Us with sufficient detail to enable Us to delete that information.


The CCPA provides California residents with specific rights regarding their personal information. If You are a resident of California, You have the following rights:

  • The right to notice. You have the right to be notified which categories of Personal Data are being collected and the purposes for which the Personal Data is being used.
  • The right to request. Under CCPA, You have the right to request that We disclose information to You about Our collection, use, sale, disclosure for business purposes and share of personal information. Once We receive and confirm Your request, We will disclose to You:
    • The categories of personal information We collected about You
    • The categories of sources for the personal information We collected about You
    • Our business or commercial purpose for collecting or selling that personal information
    • The categories of third parties with whom We share that personal information
    • The specific pieces of personal information We collected about You
    • If we sold Your personal information or disclosed Your personal information for a business purpose, We will disclose to You:
      • The categories of personal information categories sold
      • The categories of personal information categories disclosed
  • The right to say no to the sale of Personal Data (opt-out). You have the right to direct Us to not sell Your personal information. To submit an opt-out request please contact Us.
  • The right to delete Personal Data. You have the right to request the deletion of Your Personal Data, subject to certain exceptions. Once We receive and confirm Your request, We will delete (and direct Our Service Providers to delete) Your personal information from our records, unless an exception applies. We may deny Your deletion request if retaining the information is necessary for Us or Our Service Providers to:
    • Complete the transaction for which We collected the personal information, provide a good or service that You requested, take actions reasonably anticipated within the context of our ongoing business relationship with You, or otherwise perform our contract with You.
    • Detect security incidents, protect against malicious, deceptive, fraudulent, or illegal activity, or prosecute those responsible for such activities.
    • Debug products to identify and repair errors that impair existing intended functionality.
    • Exercise free speech, ensure the right of another consumer to exercise their free speech rights, or exercise another right provided for by law.
    • Comply with the California Electronic Communications Privacy Act (Cal. Penal Code § 1546 et. seq.).
    • Engage in public or peer-reviewed scientific, historical, or statistical research in the public interest that adheres to all other applicable ethics and privacy laws, when the information’s deletion may likely render impossible or seriously impair the research’s achievement, if You previously provided informed consent.
    • Enable solely internal uses that are reasonably aligned with consumer expectations based on Your relationship with Us.
    • Comply with a legal obligation.
    • Make other internal and lawful uses of that information that are compatible with the context in which You provided it.
  • The right not to be discriminated against. You have the right not to be discriminated against for exercising any of Your consumer’s rights, including by:
    • Denying goods or services to You
    • Charging different prices or rates for goods or services, including the use of discounts or other benefits or imposing penalties
    • Providing a different level or quality of goods or services to You
    • Suggesting that You will receive a different price or rate for goods or services or a different level or quality of goods or services


In order to exercise any of Your rights under the CCPA, and if You are a California resident, You can contact Us:

  • By email:

Only You, or a person registered with the California Secretary of State that You authorize to act on Your behalf, may make a verifiable request related to Your personal information.

Your request to Us must:

  • Provide sufficient information that allows Us to reasonably verify You are the person about whom We collected personal information or an authorized representative
  • Describe Your request with sufficient detail that allows Us to properly understand, evaluate, and respond to it

We cannot respond to Your request or provide You with the required information if We cannot:

  • Verify Your identity or authority to make the request
  • And confirm that the personal information relates to You

We will disclose and deliver the required information free of charge within 45 days of receiving Your verifiable request. The time period to provide the required information may be extended once by an additional 45 days when reasonably necessary and with prior notice.

Any disclosures We provide will only cover the 12-month period preceding the verifiable request’s receipt.

For data portability requests, We will select a format to provide Your personal information that is readily usable and should allow You to transmit the information from one entity to another entity without hindrance.


You have the right to opt-out of the sale of Your personal information. Once We receive and confirm a verifiable consumer request from You, we will stop selling Your personal information. To exercise Your right to opt-out, please contact Us.

The Service Providers we partner with (for example, our analytics or advertising partners) may use technology on the Service that sells personal information as defined by the CCPA law. If you wish to opt out of the use of Your personal information for interest-based advertising purposes and these potential sales as defined under CCPA law, you may do so by following the instructions below.

Please note that any opt out is specific to the browser You use. You may need to opt out on every browser that You use.


You can opt out of receiving ads that are personalized as served by our Service Providers by following our instructions presented on the Service:

The opt out will place a cookie on Your computer that is unique to the browser You use to opt out. If you change browsers or delete the cookies saved by your browser, You will need to opt out again.


Your mobile device may give You the ability to opt out of the use of information about the apps You use in order to serve You ads that are targeted to Your interests:

  • “Opt out of Interest-Based Ads” or “Opt out of Ads Personalization” on Android devices
  • “Limit Ad Tracking” on iOS devices

You can also stop the collection of location information from Your mobile device by changing the preferences on Your mobile device.


Our Service does not respond to Do Not Track signals.

However, some third party websites do keep track of Your browsing activities. If You are visiting such websites, You can set Your preferences in Your web browser to inform websites that You do not want to be tracked. You can enable or disable DNT by visiting the preferences or settings page of Your web browser.


The Service may contain content appropriate for children under the age of 13. As a parent, you should know that through the Service children under the age of 13 may participate in activities that involve the collection or use of personal information. We use reasonable efforts to ensure that before we collect any personal information from a child, the child’s parent receives notice of and consents to our personal information practices.

We also may limit how We collect, use, and store some of the information of Users between 13 and 18 years old. In some cases, this means We will be unable to provide certain functionality of the Service to these Users. If We need to rely on consent as a legal basis for processing Your information and Your country requires consent from a parent, We may require Your parent’s consent before We collect and use that information.

We may ask a User to verify its date of birth before collecting any personal information from them. If the User is under the age of 13, the Service will be either blocked or redirected to a parental consent process.


The Company may collect and store persistent identifiers such as cookies or IP addresses from Children without parental consent for the purpose of supporting the internal operation of the Service.

We may collect and store other personal information about children if this information is submitted by a child with prior parent consent or by the parent or guardian of the child.

The Company may collect and store the following types of personal information about a child when submitted by a child with prior parental consent or by the parent or guardian of the child:

  • First and/or last name
  • Date of birth
  • Gender
  • Grade level
  • Email address
  • Telephone number
  • Parent’s or guardian’s name
  • Parent’s or guardian’s email address

For further details on the information We might collect, You can refer to the “Types of Data Collected” section of this Privacy Policy. We follow our standard Privacy Policy for the disclosure of personal information collected from and about children.


A parent who has already given the Company permission to collect and use his child personal information can, at any time:

  • Review, correct or delete the child’s personal information
  • Discontinue further collection or use of the child’s personal information

To make such a request, You can write to Us using the contact information provided in this Privacy Policy.


Under California Civil Code Section 1798 (California’s Shine the Light law), California residents with an established business relationship with us can request information once a year about sharing their Personal Data with third parties for the third parties’ direct marketing purposes.

If you’d like to request more information under the California Shine the Light law, and if You are a California resident, You can contact Us using the contact information provided below.


California Business and Professions Code Section 22581 allows California residents under the age of 18 who are registered users of online sites, services or applications to request and obtain removal of content or information they have publicly posted.

To request removal of such data, and if You are a California resident, You can contact Us using the contact information provided below, and include the email address associated with Your account.

Be aware that Your request does not guarantee complete or comprehensive removal of content or information posted online and that the law may not permit or require removal in certain circumstances.


Our Service may contain links to other websites that are not operated by Us. If You click on a third party link, You will be directed to that third party’s site. We strongly advise You to review the Privacy Policy of every site You visit.

We have no control over and assume no responsibility for the content, privacy policies or practices of any third party sites or services.


We may update Our Privacy Policy from time to time. We will notify You of any changes by posting the new Privacy Policy on this page.

We will let You know via email and/or a prominent notice on Our Service, prior to the change becoming effective and update the “Last updated” date at the top of this Privacy Policy.

You are advised to review this Privacy Policy periodically for any changes. Changes to this Privacy Policy are effective when they are posted on this page.


If you have any questions about this Privacy Policy, You can contact us:

  • By email: