---
title: Free Tools - Scholar Sidekick
description: Free web tools for working with scholarly identifiers, citations, and bibliographic metadata. No signup required.
doc_version: "1.0"
last_updated: "2026-04-16"
---

# Free Tools

> Small, focused web tools for working with scholarly identifiers and citations. Each tool is free to use and requires no signup.
> HTML version: https://scholar-sidekick.com/tools
> Last updated: 2026-04-16

## Tools

- [Citation Verifier](https://scholar-sidekick.com/tools/citation-verifier) ([markdown](https://scholar-sidekick.com/tools/citation-verifier.md)) - Paste a citation. The verifier resolves the identifier, compares the resolved title to the cited title, and flags fabricated citations (real DOI + invented title - the Topaz et al. Lancet 2026 pattern).
- [Scholarly Identifier Detector](https://scholar-sidekick.com/tools/identifier-detector) ([markdown](https://scholar-sidekick.com/tools/identifier-detector.md)) - Paste any text and instantly find every DOI, PubMed ID, PMCID, arXiv ID, ISBN, ISSN, ADS bibcode, and scholarly URL it contains.
- [DOI Lookup](https://scholar-sidekick.com/tools/doi-lookup) ([markdown](https://scholar-sidekick.com/tools/doi-lookup.md)) - Enter a DOI, PMID, or any identifier and instantly see the full metadata: title, authors, journal, year, and identifiers.
- [PMID / PMCID / DOI Converter](https://scholar-sidekick.com/tools/pubmed-id-converter) ([markdown](https://scholar-sidekick.com/tools/pubmed-id-converter.md)) - Enter a PMID, PMCID, or DOI and instantly get the other two identifiers. Essential for NIH grant applications and cross-database lookups.
- [DOI to BibTeX Generator](https://scholar-sidekick.com/tools/doi-to-bibtex) ([markdown](https://scholar-sidekick.com/tools/doi-to-bibtex.md)) - Enter a DOI, PubMed ID, arXiv ID, or any scholarly identifier and instantly get a formatted BibTeX entry ready to paste into a .bib file.
- [DOI to RIS Converter](https://scholar-sidekick.com/tools/doi-to-ris) ([markdown](https://scholar-sidekick.com/tools/doi-to-ris.md)) - Enter any scholarly identifier and download an RIS file you can import into Zotero, Mendeley, EndNote, or any reference manager.
- [Open Access Checker](https://scholar-sidekick.com/tools/open-access-checker) ([markdown](https://scholar-sidekick.com/tools/open-access-checker.md)) - Check if a paper is open access. Enter any identifier and see where to read it for free. Powered by Unpaywall.
- [Retraction Checker](https://scholar-sidekick.com/tools/retraction-checker) ([markdown](https://scholar-sidekick.com/tools/retraction-checker.md)) - Check if a paper has been retracted, corrected, or flagged with an expression of concern. Powered by Retraction Watch via Crossref.
- [Citation Style Comparator](https://scholar-sidekick.com/tools/citation-style-comparator) ([markdown](https://scholar-sidekick.com/tools/citation-style-comparator.md)) - Compare how the same paper looks in Vancouver, APA, AMA, IEEE, and CSE. Enter any identifier and see formatted citations side by side.
- [Identifier Validator](https://scholar-sidekick.com/tools/identifier-validator) ([markdown](https://scholar-sidekick.com/tools/identifier-validator.md)) - Check if a DOI, PMID, ISBN, or other scholarly identifier is valid and resolvable. See the detected type, canonical form, and whether it returns real metadata.

## More tools

Looking for the main citation formatting tool? Use the [Scholar Sidekick resolver](https://scholar-sidekick.com) to format DOIs, PMIDs, and more into Vancouver, APA, AMA, IEEE, CSE, or any of 10,000+ CSL styles, and export them to RIS, BibTeX, and more. See the [API documentation](https://scholar-sidekick.com/docs) if you want to build on top of Scholar Sidekick, or the [MCP server](https://scholar-sidekick.com/mcp) for AI-assistant integrations.

## Sitemap

See the full [sitemap](https://scholar-sidekick.com/sitemap.md) for all pages.