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Zotero Server Read API

This is version 1 of the Zotero Web API. For new development, use API version 3.

The Read API, part of the Zotero Web API, provides read-only access to online Zotero libraries.

Base URL

The base URL for all API requests is

All requests must use HTTPS rather than HTTP.

API Versioning

Every Atom response includes the current API version. Requests may include the version parameter to specify the API version used to interact with the server. After the introduction of a new API version, older API versions will remain available for a yet-to-be-determined period.


Accessing non-public data via the API requires use of an API key. Third-party developers should use OAuth to establish credentials or instruct their users to create dedicated keys for use with their services. End users can create API keys via their Zotero account settings.

GET Requests

Requests for data in a specific library begin with /users/<userID> or /groups/<groupID>. User IDs are different from usernames and can be found on the API Keys page and in OAuth responses.

Requests for "/users/<userID>" or "/groups/<groupID>"

URI Description
<userOrGroupPrefix>/items The set of all items in the library
<userOrGroupPrefix>/items/top The set of all top-level items in the library
<userOrGroupPrefix>/items/trash The set of items in the trash
<userOrGroupPrefix>/items/<itemKey> A specific item in the library
<userOrGroupPrefix>/items/<itemKey>/children The set of all child items under a specific item
<userOrGroupPrefix>/items/<itemKey>/tags The set of all tags associated with a specific item
<userOrGroupPrefix>/tags The set of all tags in the library
<userOrGroupPrefix>/tags/<url+encoded+tag> The set of tags (i.e., of all types) matching a specific name
<userOrGroupPrefix>/collections The set of collections in the library
<userOrGroupPrefix>/collections/top The set of all top-level collections in the library
<userOrGroupPrefix>/collections/<collectionKey> A specific collection in the library
<userOrGroupPrefix>/collections/<collectionKey>/collections The set of subcollections within a specific collection in the library
<userOrGroupPrefix>/collections/<collectionKey>/items The set of items within a specific collection in the library
<userOrGroupPrefix>/collections/<collectionKey>/tags The set of tags within a specific collection in the library

Requests Specific to "/users/<userID>"

URI Description
/users/<userID>/groups The set of groups the current API key has access to, including public groups the key owner belongs to even if the key doesn't have explicit permissions for it.
/users/<userID>/keys/<key> The privileges of the given API key.

URL Parameters

All parameters are optional.

Parameters for All Requests

Parameter Values Default Description
format “atom”, “bib”, “keys”, export formats “atom” “atom” will return an Atom feed.
“bib”, valid only for item requests, will return a formatted bibliography as XHTML. “bib” mode is currently limited to a maximum of 150 items.
“keys”, valid only for multi-item requests, will return a newline-separated list of item keys. “keys” mode has no default or maximum limit.
Export formats, valid only for item requests, produce output in the specified format. The 'limit' parameter is required for multi-item export format requests.
key string null If a valid API key is provided, the request will be processed with the identity of the key's owner and the authority granted to the key.
version integer null If a developer wishes to use a version of the API other than the latest available version, they can pass the desired version. If the requested method is no longer supported for the passed version, the server will return an error message and an HTTP status code of 400.

Search Parameters

Parameter Values Default Description
itemKey string null A comma-separated list of item keys. Valid only for item requests. Up to 50 items can be specified in a single request.
q string null Field search. Currently searches titles and individual creator fields
itemType search syntax null Item type search
tag search syntax search syntax Tag search

Search Syntax

itemType and tag parameters support Boolean searches:


  • “itemType=book”
  • “itemType=book || journalArticle” (OR)
  • “itemType=-attachment” (NOT)
  • “tag=foo”
  • “tag=foo bar” (tag with space)
  • “tag=foo&tag=bar” (AND)
  • “tag=foo bar || bar” (OR)
  • “tag=-foo” (NOT)
  • “tag=\-foo” (literal first-character hyphen)

Parameters for "format=atom", "format=keys", and "format={export_format}"

The following parameters are valid only when accessing a resource that represents a set of objects. For example, /users/123/items represents a set of items, while /users/123/items/ABCD2345 represents a single item.

Parameter Values Default Description
order “dateAdded”, “dateModified”, “title”, “creator”, “type”, “date”, “publisher”, “publicationTitle”, “journalAbbreviation”, “language”, “accessDate”, “libraryCatalog”, “callNumber”, “rights”, “addedBy”, “numItems” (tags) dateAdded The name of the field by which entries are ordered
sort “asc”, “desc” varies by “order” The sorting direction of the field specified in the order parameter
limit integer 1-100* 50* The maximum number of results to return with a single request. Required for export formats.
start integer 0 The index of the first result. Combine with the limit parameter to select a slice of the available results.

* Applies to format=atom and format={export_format} only. format=keys has no default or maximum limit.

Parameters for "format=atom" and "format={export_format}"

Parameter Values Default Description
pprint boolean false format=atom: Outputs the response with content type “text/xml” instead of “application/atom+xml” and adds a long comment before to disable Firefox's feed auto-detection.
format={export_format}: Outputs the response with content type “text/plain” for easier display in browsers.

Parameters for "format=atom"

Parameter Values Default Description
content “html”, “json”, “bib”, export formats, “none”
Multiple formats can be specified by using a comma as the delimiter (“content=json,bib”).
“html” The format of the Atom response's <content> node:
“html” (the default) will return an XHTML representation of each object, useful for display in feed readers and for parsing by XML tools.
“json”, currently valid only for item and collection requests, will return a JSON representation of all the item's fields.
“bib”, valid only for item requests, will return a formatted reference for each item.
Export formats, valid only for item requests, will return data in the specified format for each item.
If additional data is not required, use “none” to decrease the response size.
If multiple formats are requested, <content> will contain multiple <zapi:subcontent> elements (in the namespace), each with a zapi:type attribute matching one of the specified content parameters.

Parameters for "format=bib" and "content=bib"

Parameter Values Default Description
style string “chicago-note-bibliography” Citation style to use for formatted references. Should be the file name (without the “.csl” extension) of one of the default styles in the Zotero Style Repository (e.g., “apa” for Support for other styles is forthcoming.

Note the difference between format=bib and content=bib. format=bib returns a formatted bibliography as XHTML, sorted according to the rules of the selected style. content=bib (valid only for format=atom, the default format mode) returns an individual formatted reference within the Atom <content> block for each item, with the Atom feed sorted according to the query parameters. format=bib processes the entire feed you are requesting without regard for any limit arguments, so it is generally a good idea to use it only with collections or tags.

Export Formats

The following bibliographic data formats can be used as 'format' and 'content' parameters:

Parameter Description
bibtex BibTeX
bookmarks Netscape Bookmark Format
coins COinS
csljson Citation Style Language data format
mods MODS
refer Refer/BibIX
rdf_bibliontology Bibliographic Ontology RDF
rdf_dc Unqualified Dublin Core RDF
rdf_zotero Zotero RDF
ris RIS
tei Text Encoding Initiative (TEI)
wikipedia Wikipedia Citation Templates

Example Requests and Responses

Several examples of Read API request URLs and their responses:

Atom feed - List of collections for a user

Write API

The Read API is accompanied by a Write API, which allows for the creation, modification and deletion of items and collections in online Zotero libraries.

HTTP Status Codes

Successful GET requests will return a 200 OK status code.

Conditional GET requests using If-Modified-Since or If-Match may return a 304 Not Modified if the requested resource has not changed since the specified time/version. 304 responses may not yet be implemented for all requests.

For any read or write request, the server may return a 400 Bad Request, 404 Not Found, or 405 Method Not Allowed for an invalid request and 500 Internal Server Error or 503 Service Unavailable for a server-related issue. Authentication errors (e.g., invalid API key or insufficient privileges) will return a 403 Forbidden.

Passing an Expect header, which is unsupported, will result in a 417 Expectation Failed response.