Paste a paragraph, reference list, or manuscript excerpt. We’ll find every DOI, PMID, arXiv ID, ISBN, and more.
We’ll detect every DOI, PMID, PMCID, arXiv ID, ISBN, ISSN, and NASA ADS bibcode. Nothing is stored.
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A scholarly identifier is a unique code used to permanently locate and cite an academic publication. Unlike titles or author names - which can be ambiguous, vary between databases, or change over time - identifiers never change and always point to one specific work. They are the backbone of reproducible citation and interoperability between reference databases, publishers, and reference managers.
If you work with scholarly literature long enough, you will run into several different identifier schemes. Each one was invented by a different community for a different purpose, and most of them are still in active use today. This tool recognises all the major ones.
Scholar Sidekick detects all of the following, including labelled forms (e.g. PMID: 12345), bare tokens, doi.org and PubMed URLs, and BibTeX fields.
| Type | Example | Source |
|---|---|---|
| DOI | 10.1038/nature12373 | CrossRef, publishers |
| PMID | 23831765 | PubMed / NCBI |
| PMCID | PMC3737249 | PubMed Central |
| arXiv ID | 2209.14430v2 | arXiv.org |
| ISBN | 978-0-306-40615-7 | Books |
| ISSN | 0028-0836 | Journals (print) |
| eISSN | 1476-4687 | Journals (electronic) |
| ADS bibcode | 2023Natur.615..123W | NASA Astrophysics Data System |
DOIs are the most widely used scholarly identifier. They are assigned by CrossRef and other registration agencies, and every modern journal article, preprint, or data set should have one. A DOI always starts with 10. followed by a registrant code, a slash, and a suffix. This tool recognises bare DOIs, doi.org URLs, spaced DOIs (e.g. in PDFs), and DataCite arXiv DOIs.
A PMID is the numeric ID used by the PubMed biomedical citation database, maintained by the US National Library of Medicine. It identifies a record in PubMed rather than a full-text article, so a single paper may have both a DOI (pointing at the publisher) and a PMID (pointing at the PubMed record). The tool detects labelled forms (PMID: 12345678) and PubMed URLs.
A PMCID identifies a full-text article in PubMed Central, the open-access repository operated by the NIH. A paper may have a PMID but no PMCID (if the full text is not available in PMC), or both. PMCIDs always look like PMC followed by digits (e.g. PMC3737249).
arXiv.org hosts preprints across physics, mathematics, computer science, and more. Modern arXiv IDs take the form YYMM.NNNNN (e.g. 2209.14430), optionally followed by a version suffix (v2). Older papers use a legacy category scheme (cs.CL/0301001). The tool detects both schemes, arXiv URLs, and BibTeX eprint fields.
ISBNs identify published books. The tool recognises labelled 10- and 13-digit ISBNs with or without dashes (e.g. 978-0-306-40615-7) and normalises the result. Use the identifier detector to pull every ISBN out of a reference list in one go - much faster than hunting through the text by hand.
ISSNs identify serial publications - journals, magazines, newspapers - rather than individual articles. A print journal has an ISSN; its electronic counterpart has an eISSN. Both are 8-digit codes in the form NNNN-NNNX. The detector validates the check digit, so only well-formed ISSNs are returned.
Astronomers and astrophysicists use 19-character bibcodes from the NASA Astrophysics Data System (ADS). A bibcode encodes year, journal, volume, and page in a single token (e.g. 2023Natur.615..123W). The detector recognises both bare bibcodes and the ADS: labelled form.
Each identifier can be resolved to full bibliographic metadata - title, authors, journal, year, volume, pages - and then formatted as a citation in any style. You can also export the results to BibTeX, RIS, CSL JSON, EndNote XML, or CSV for import into reference managers like Zotero, Mendeley, or EndNote. The same resolver and exporter stack powers the main Scholar Sidekick site, the public API, and the MCP integration.
Paste anything. The detector handles:
10.1038/nature12373)PMID: 12345678, PMCID: PMC3737249)https://doi.org/10.1038/nature12373, pubmed.ncbi.nlm.nih.gov/23831765)doi = {10.1038/nature12373}, eprint = {2209.14430})A PMID identifies a record in PubMed, the citation database. A PMCID identifies the full-text article in PubMed Central, the open-access repository. A paper can have a PMID without a PMCID (common when the full text is not open-access), or both. They are different identifiers - always check which one you need before citing.
DOIs must start with 10. followed by a registrant code and a suffix. If you pasted a shortened or mangled form (e.g. without the 10. prefix), the detector will not find it. Paste the full DOI or a doi.org URL.
You can paste text extracted from a PDF. The tool accepts up to 10,000 characters at a time. For longer documents, extract and paste the reference section on its own - that’s where almost all the identifiers live.
Yes. No account required. It runs entirely inside Scholar Sidekick’s own infrastructure, and nothing you paste is stored.
No - this tool only detects identifiers. It does not make any outbound requests to CrossRef, PubMed, or any other database. If you want full bibliographic metadata or a formatted citation, use the main Scholar Sidekick resolver or the /api/format endpoint.