What the DOI Metadata Lookup does
This DOI lookup fetches the public metadata registered for a Digital Object Identifier - title, authors, journal, volume, pages, dates, publisher, licence and funders - from Crossref, or from DataCite for datasets and repository records, and turns it into BibTeX, RIS and a formatted reference in APA, MLA, Chicago, Harvard or IEEE style.
Only the DOI itself is sent, through a2z.tools' read-only fetcher, to the registration agencies' public REST APIs. Formatting happens in your browser, and when a record cannot be fetched the tool says so rather than showing an empty or guessed result.
How to use it
- Paste up to ten DOIs, one per line. Bare DOIs, doi: prefixes and https://doi.org/ links all work; anything that is not a DOI is skipped and never sent.
- Choose the reference style you want for the formatted version.
- Choose Look up. Each DOI is tried at Crossref first, which registers most journal articles, books and conference papers, then at DataCite, which registers most datasets, software and repository deposits.
- Read the metadata table for each DOI, open the abstract where the publisher has deposited one, and copy the reference or BibTeX.
- Download all the found records together as BibTeX, RIS or CSV to import into Zotero, Mendeley or EndNote.
Reading the results
The metadata is exactly what the publisher or repository deposited with the registration agency. If a title has odd capitalisation or an author's name is incomplete, that is how it was registered - correct it in your reference manager after import.
"Cited by" is the agency's own count (Crossref's is-referenced-by-count, for example). It only counts citations from other deposited reference lists, so it is usually lower than Google Scholar or Scopus and should not be compared with them.
Unavailable means the agency could not be reached or answered with an error; it is not the same as not found. Not found means neither Crossref nor DataCite has the DOI.
Worked example: turning one DOI into a reference
Entering https://doi.org/10.1037/0003-066X.59.1.29 sends only 10.1037/0003-066X.59.1.29 to Crossref. The record comes back as a journal article: "How the Mind Hurts and Heals the Body." by Oakley Ray, American Psychologist, volume 59, issue 1, pages 29-40, 2004, published by the American Psychological Association.
In APA 7 it becomes: Ray, O. (2004). How the Mind Hurts and Heals the Body. American Psychologist, 59(1), 29-40. https://doi.org/10.1037/0003-066x.59.1.29 - note that the title keeps the capitalisation Crossref holds, so for APA you would change it to sentence case yourself.
A Zenodo DOI such as 10.5281/zenodo.3509134 is not at Crossref (it answers 404), so the tool asks DataCite, which returns the deposit's creators, title, year, publisher (Zenodo) and licence.
Crossref, DataCite and the other agencies
A DOI is handed out by one of several registration agencies, and the metadata lives with that agency. Crossref covers most scholarly publishers, DataCite most research data and repositories. Together they hold the great majority of DOIs a researcher meets.
Some DOIs belong to other agencies such as mEDRA (European publishers), JaLC (Japan) or CNKI (China). They still resolve at doi.org, but their metadata is not read here, so the tool reports them as not found rather than inventing a record.
Limitations: what the result does not prove
- Metadata quality depends on the depositor. Missing issues, pages, abstracts or ORCID iDs are common and cannot be filled in by this tool.
- Only Crossref and DataCite are queried. The tool cannot see paywalled full text, retraction notices beyond what is deposited, or citation counts from commercial databases.
- Titles are shown as registered; the formatted reference does not change capitalisation to match a style's sentence- or title-case rule.
- Up to ten DOIs are looked up at a time, one after another, and a rate limit applies to protect the public APIs.
Privacy: where your data goes
a2z.tools requests the public address you enter with an ordinary read-only GET, the way a browser would, and analyses the response. Private and internal addresses are refused. Nothing is stored. The DOI you enter is looked up in the public Crossref or DataCite REST API through a2z.tools' read-only fetcher; formatting happens in your browser. Only the DOI is sent. Session recording and tag-manager scripts are switched off on this page.
Standards and sources
- Crossref REST API - checked 19 Sep 2026
- DataCite REST API - checked 19 Sep 2026
- DOI Handbook (International DOI Foundation) - checked 19 Sep 2026
Frequently asked questions
How do I convert a DOI to BibTeX?
Paste the DOI and choose Look up. The BibTeX appears under each record, and Download BibTeX saves all found records in one .bib file that LaTeX, Overleaf and reference managers can import.
Why does my DOI say not found?
Check for typing errors first: a DOI starts with 10., has a prefix of four or more digits, a slash, then a suffix. If it is correct, it is probably registered with an agency other than Crossref or DataCite, or it was never registered at all.
Is the metadata live?
Yes, each lookup asks the agency's public API at the time you click. Nothing is cached or stored by the tool, so a correction the publisher makes appears the next time you look it up.
What is sent when I look up a DOI?
Only the DOI string, as part of the request to api.crossref.org or api.datacite.org, fetched through a2z.tools' read-only fetcher. Other lines you paste are not sent, and no account or cookie is involved.
Can I look up an ISBN or PubMed ID here?
No. This tool reads DOIs only. Many books and PubMed articles also have a DOI, often printed on the copyright page or article landing page; look that up instead.
Why is the cited-by number different from Google Scholar?
Each database counts citations from its own set of sources. Crossref counts only citations in reference lists deposited with Crossref, while Google Scholar crawls the wider web, so Scholar is usually higher.
Last reviewed by the A2Z.Tools team against the sources listed above.
