Wikidata:Data access

Wikidata currently contains over 100 million Items and over 650,000 Lexemes, and these numbers will keep on growing. There are many methods available to access all that data -- this document lays them out and helps prospective users choose the best method to suit their needs.

It's crucial to choose an access method that gives you the data you need in the quickest, most efficient way while not putting unnecessary load on Wikidata; this page is here to help you do just that.

Before we begin

Using Wikidata's data

 
Our logo

Wikidata offers a wide range of general data about everything under the sun. All that data is licensed CC0, "No rights reserved", for the public domain.

Changes to APIs and other methods of accessing Wikidata are subject to the Stable Interface Policy. Data sources on this page are not guaranteed to be stable interfaces.

Wikimedia projects

This document is about accessing data from outside Wikimedia projects. If you need to present data from Wikidata in another Wikimedia project, where you can employ parser functions, Lua and/or other internal-only methods, refer to How to use data on Wikimedia projects.

Data best practices

 
Volunteers like these people – and you – make Wikidata

We offer the data in Wikidata freely and with no requirement for attribution under CC-0. In return, we would greatly appreciate it if, in your project, you mention Wikidata as the origin of your data. In so doing you help ensure that Wikidata will stay around for a long time to provide up-to-date and high-quality data. We also promote the best projects that use Wikidata's data.

Some examples for attributing Wikidata: "Powered by Wikidata", "Powered by Wikidata data", "Powered by the magic of Wikidata", "Using Wikidata data", "With data from Wikidata", "Data from Wikidata", "Source: Wikidata", "Including data from Wikidata" and so forth. You can also use one of our ready-made files.

You may use the Wikidata logo shown above, but in so doing you should not in any way imply endorsement by Wikidata or by the Wikimedia Foundation.

Please offer your users a way to report issues in the data, and find a way to feed this back to Wikidata's editor community, for example through the Mismatch Finder. Please share the location where you collect these issues on the Project chat.

Access best practices

When accessing Wikidata's data, observe the following best practices:

  • Follow the User-Agent policy -- send a good User-Agent header.
  • Follow the robot policy: send Accept-Encoding: gzip,deflate and don’t make too many requests at once.
  • If you get a 429 Too Many Requests response, stop sending further requests for a while (see the Retry-After response header)
  • When available (such as with the Wikidata Query Service), set the lowest timeout that makes sense for your data.
  • When using the MediaWiki Action API, make liberal use of the maxlag parameter and consult the rest of the guidelines laid out in API:Etiquette.

Search

What is it?

Wikidata offers an Elasticsearch index for traditional searches through its data: Special:Search

When to use it?

Use search when you need to look for a text string, or when you know the names of the entities you're looking for but not the exact entities themselves. It's also suitable for cases in which you can specify your search based on some very simple relations in the data.

Don't use search when the relations in your data are better described as complex.

Details

You can make your search more powerful with these additional keywords specific to Wikidata: haswbstatement, inlabel, wbstatementquantity, hasdescription, haslabel. This search functionality is documented on the CirrusSearch extension page. It also has its own API action.

Linked Data Interface (URI)

What is it?

The Linked Data Interface provides access to individual entities via URI: http://www.wikidata.org/entity/Q???

When to use it?

Use the Linked Data Interface when you need to obtain individual, complete entities that are already known to you.

Don't use it when you're not clear on which entities you need -- first try searching or querying. It's also not suitable for requesting large quantities of data.

Details

 
Meet Q42

Each Item or Property has a persistent URI made up of the Wikidata concept namespace and the Item or Property ID (e.g., Q42, P31) as well as concrete data that can be accessed by that Item's or Property's data URL.

The namespace for Wikidata's data about entities is https://wikidata.org/wiki/Special:EntityData.

Appending an entity's ID to this prefix (you can use /entity/ for short) creates the abstract (format-neutral) form of the entity's data URL. When accessing a resource in the Special:EntityData namespace, the special page applies content negotiation to determine the output format. If you opened the resource in a browser, you'll see an HTML page containing data about the entity, because web browsers prefer HTML. However, a linked-data client would receive the entity data in a format like JSON or RDF -- whatever the client specifies in its HTTP Accept: header.

For example, take this concept URI for Douglas Adams -- that's a reference to the real-world person, not to Wikidata's concrete description:
http://www.wikidata.org/entity/Q42
As a human being with eyes and a browser, you will likely want to access data about Douglas Adams by using the concept URI as a URL. Doing so triggers an HTTP redirect and forwards the client to the data URL that contains Wikidata's data about Douglas Adams: https://www.wikidata.org/wiki/Special:EntityData/Q42.

When you need to bypass content negotiation, say, in order to view non-HTML content in a web browser, you can specify the format of the entity data by appending the corresponding extension to the data URL; examples include .json, .rdf, .ttl, .nt or .jsonld. For example, https://www.wikidata.org/wiki/Special:EntityData/Q42.json gives you Item Q42 in JSON format.

Less verbose RDF output

By default, the RDF data that the Linked Data interface returns is meant to be complete in itself, so it includes descriptions of other entities it refers to. If you want to exclude that information, you can append the query parameter ?flavor=dump to the URL(s) you request.

By appending &flavor to the URL, you can control exactly what kind of data gets returned.

  • ?flavor=dump: Excludes descriptions of entities referred to in the data.
  • ?flavor=simple: Provides only truthy statements (best-ranked statements without qualifiers or references), along with sitelinks and version information.
  • ?flavor=full (default): An argument of "full" returns all data. (You don't need to specify this because it's the default.)

If you want a deeper insight into exactly what each option entails, you can take a peek into the source code.

Revisions and caching

You can request specific revisions of an entity with the revision query parameter: https://www.wikidata.org/wiki/Special:EntityData/Q42.json?revision=112.

The following URL formats are used by the user interface and by the query service updater, respectively, so if you use one of the same URL formats there’s a good chance you’ll get faster (cached) responses:

Wikidata Query Service

What is it?

The Wikidata Query Service (WDQS) is Wikidata's own SPARQL endpoint. It returns the results of queries made in the SPARQL query language: https://query.wikidata.org

When to use it?

Use WDQS when you know only the characteristics of your desired data.

Don't use WDQS for performing text or fuzzy search -- FILTER(REGEX(...)) is an antipattern. (Use search in such cases.)

WDQS is also not suitable when your desired data is likely to be large, a substantial percentage of all Wikidata's data. (Consider using a dump in such cases.)

Details

You can query the data in Wikidata through our SPARQL endpoint, the Wikidata Query Service. The service can be used both as an interactive web interface, or programmatically by submitting GET or POST requests to https://query.wikidata.org/sparql.

The query service is best used when your intended result set is scoped narrowly, i.e., when you have a query you're pretty sure already specifies your resulting data set accurately. If your idea of the result set is less well defined, then the kind of work you'll be doing against the query service will more resemble a search; frequently you'll first need to do this kind of search-related work to sharpen up your query. See the Search section.

Linked Data Fragments endpoint

What is it?

The Linked Data Fragments (LDF) endpoint is a more experimental method of accessing Wikidata's data by specifying patterns in triples: https://query.wikidata.org/bigdata/ldf. Computation occurs primarily on the client side.

When to use it?

Use the LDF endpoint when you can define the data you're looking for using triple patterns, and when your result set is likely to be fairly large. The endpoint is good to use when you have significant computational power at your disposal.

Since it's experimental, don't use the LDF endpoint if you need an absolutely stable endpoint or a rigorously complete result set. And as mentioned before, only use it if you have sufficient computational power, as the LDF endpoint offloads computation to the client side.

Details

If you have partial information about what you're looking for, such as when you have two out of three components of your triple(s), you may find what you're looking for by using the Linked Data Fragments interface at https://query.wikidata.org/bigdata/ldf. See the user manual and community pages for more information.

MediaWiki Action API

What is it?

The Wikidata API is MediaWiki's own Action API, extended to include some Wikibase-specific actions: https://wikidata.org/w/api.php

When to use it?

Use the API when your work involves editing Wikidata. It's also suitable for situations when you need small groups of entities in JSON format (up to 50 entities per request).

Don't use the API when your result set is likely to be large. (Consider using a dump in such cases.)

The API is also poorly suited to situations in which you want to request the current state of entities in JSON. (For such cases consider using the Linked Data Interface, which is likelier to provide faster responses.)

Finally, it's probably a bad idea to use the API when you'll need to further narrow the result of your API request. In such cases it's better to frame your work as a search (for Elasticsearch) or a query (for WDQS).

Details

The MediaWiki Action API used for Wikidata is meticulously documented on Wikidata's API page. You can explore and experiment with it using the API Sandbox.

Bots

 
We welcome well-behaved bots

You can also access the API by using a bot. For more on bots, see Wikidata:Bots.

Recent Changes stream

What is it?

The Recent Changes stream provides a continuous stream of changes of all Wikimedia wikis, including Wikidata: https://stream.wikimedia.org

When to use it?

Use the Recent Changes stream when your project requires you to react to changes in real time or when you need all the latest changes coming from Wikidata -- for example, when running your own query service.

Details

The Recent Changes stream contains all updates from all wikis using the server-sent events protocol. You'll need to filter Wikidata's updates out on the client side.

You can find the web interface at stream.wikimedia.org and read all about it on the EventStreams page.

Dumps

What are they?

Wikidata dumps are complete exports of all the Entities in Wikidata: https://dumps.wikimedia.org

When to use them?

Use a dump when your result set is likely to be very large. You'll also find a dump important when setting up your own query service.

Don't use a dump if you need current data: the dumps take a very long time to export and even longer to sync to your own query service. Dumps are also unsuitable when you have significant limits on your available bandwidth, storage space and/or computing power.

Details

If the records you need to traverse are many, or if your result set is likely to be very large, it's time to consider working with a database dump: (link to the latest complete dump).

You'll find detailed documentation about all Wikimedia dumps on the "Data dumps" page on Meta and about Wikidata dumps in particular on the database download page. See also Flavored dumps above.

Tools

  • JsonDumpReader is a PHP library for reading dumps.
  • At [1] you'll find a Go library for processing Wikipedia and Wikidata dumps.
  • You can use wdumper to get partial custom RDF dumps.

Local query service

It's no small task to procure a Wikidata dump and implement the above tools for working with it, but you can take a further step. If you have the capacity and resources to do so, you can host your own instance of the Wikidata Query Service and query it as much as you like, out of contention with any others.

To set up your own query service, follow these instructions from the query service team, which include procuring your own local copy of the data. You may also find useful information in Adam Shorland's blog post on the topic.