Our OpenURL service is used primarily by library link resolvers but can also be used to look up metadata records. Please note that OpenURL retrieval includes only bibliographic metadata.
On this page, learn more about:
Access to the OpenURL service is free, but does require that you identify yourself.
- Crossref members and non-members: use your email address to identify yourself. You don’t need to register this with us in advance, but you do need to include it in your query.
- Librarians: if you need to use OpenURL with your library link resolver and that system requires a username and password, we can provide you with Crossref account credentials. Learn more about metadata retrieval for librarians (where you can also request your credentials).
Access using an email address
You need to include your email address in the pid parameter of the OpenURL request. Note that pid is not the same as PID (persistent identifier, such as a DOI or an ORCID iD).
For interfaces that require a key, your email address is your key.
Use the format below but include your own email address instead of firstname.lastname@example.org:
Access via a library link resolver
Log in to the library link resolver using the Crossref account credentials we provided.
The OpenURL query interface uses metadata to identify a matching DOI, and redirects the user to the target of the DOI.
For example, this query contains an author name, a journal title, volume, issue, first page, and publication year:
The OpenURL query interface matches the query with a metadata record and redirects the user to the relevant persistent identifier landing page at https://doi.org/10.1175/1520-0485(2002)032<0870:CT>2.0.CO;2.
The OpenURL Query Interface can accept these parameters:
- title (journal title)
- aulast (family name, preferably of first author)
- spage (first page)
- date (publication year YYYY)
- stitle (short title, which may be supplied as an alternative to title)
- pid (your email address). Note: pid (personal id) is different from PID (persistent identifier)
- redirect (set to false to return the DOI in XML format instead of redirecting to the target URL. The default is true)
- multihit (set to true to return DOIs for more than one content item if the Crossref system does not find an exact match. The default is false)
- format (set to unixref to return metadata in UNIXREF format)
By default, an OpenURL match will direct the user to the landing page registered for the matched metadata record.
In most instances, only a single identifier will be returned. If more than one identifier is returned, the user will be directed to a list of all available DOIs. For example, the query:
will return multiple results.
OpenURL may be used to retrieve metadata records by setting the redirect parameter to “false”. By default an OpenURL response uses the XSD XML format. The UNIXREF format may be requested by setting the format parameter to “unixref”.
This query will return an XSD-formatted XML metadata record:
There are multiple matches for this query, when multihit=true the metadata record is returned for all results:
Setting multihit=exact will return no matches:
Example DOI queries
Crossref supports DOI queries formatted as OpenURL version 0.1 requests:
Open URL query
Like metadata queries, DOI query results are returned in XML format.
NISO 0.1 or 1.0 URLs
Crossref also supports NISO 0.1 and 1.0 URLs as well as some common deviations. In general it supports the San Antonio Profile #1, including in-line, by-value, and by-reference. In the presence of a
url_ver= Z39.88-2004 parameter this service will operate on a
info:ofi/fmt:kev:mtx:ctx context format with referent formats
Simple reverse lookup
A journal article lookup
https://email@example.com&url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:journal&rft.atitle=Isolation of a common receptor for coxsackie B&rft.jtitle=Science&rft.aulast=Bergelson&rft.auinit=J&rft.date=1997&rft.volume=275&rft.spage=1320&rft.epage=1323