{CitationAPI[1]

Cite anything. Instantly.

One API call. Any URL. Perfectly formatted citations in APA, MLA, Chicago, BibTeX, and 9,000+ styles.

Get Free API Key View Documentation
Try:

Harris, C. R., Millman, K. J., van der Walt, S. J., et al. (2020). Array programming with NumPy. Nature, 585(7825), 357–362. https://doi.org/10.1038/s41586-020-2649-2

Drop-in integration

A single POST request in any language. Copy, paste, cite.

curl
curl -X POST https://api.citationapi.com/v1/citations \
  -H "Content-Type: application/json" \
  -H "X-API-Key: ca_live_your_key_here" \
  -d '{"url": "https://doi.org/10.1038/s41586-020-2649-2"}'

How it works

Three steps. No configuration. No citation formatting headaches.

1. Send a URL

POST any URL to the API — articles, books, GitHub repos, videos, arXiv papers, anything.

2. We extract & format

Our 4-layer pipeline resolves metadata from 10+ sources including Crossref, PubMed, and OpenLibrary.

3. Get your citation

Receive structured CSL-JSON metadata and pre-formatted citations in any style, in milliseconds.

What it handles

Send us any URL. We handle the rest.

Academic Journals

Crossref, PubMed

Preprints

arXiv

Books

OpenLibrary, ISBN

GitHub

Repos, issues, PRs

YouTube

Videos

Stack Overflow

Questions, answers

News & Blogs

Any webpage

9,000+ Styles

Via CiteProc-JS

Built for developers

Everything you need to add citations to your product.

9,000+ Citation Styles

APA, MLA, Chicago, IEEE, Vancouver, and thousands more via CiteProc-JS and the Citation Style Language.

Structured CSL-JSON

Get machine-readable metadata alongside formatted citations. Build reference managers, bibliographies, or research tools.

Aggressive Caching

Extract once, serve forever. Subsequent requests for the same URL return instantly from cache.

4-Layer Pipeline

Identifier resolution, meta tag parsing, LLM extraction, and proxy rendering. Multiple fallbacks ensure accuracy.

API Key Auth

Per-key rate limits, usage tracking, and key rotation. Simple X-API-Key header authentication.

High Availability

Built on PostgreSQL with JSONB storage. Designed for production workloads with 99.9% uptime SLA.

Trusted by researchers and developers

50,000+

Citations generated

9,000+

Styles supported

10+

Data sources

99.9%

Uptime SLA

Frequently asked questions

Everything you need to know about CitationAPI.

Ready to start citing?

Get your free API key and start making citation requests in seconds. No credit card required.

Get Free API Key