Crossref Metadata Search API

Beginner's Pick Books / No Auth Required Beginner HTTPS
Free to Use Varies (check documentation)
90 A+
Measured Score 0 50 100 Reachability 30/30 Speed 10/20 Security 15/15 Developer XP 20/20 Reliability 15/15 TESTED 2026-07-23

Overview

Crossref Metadata Search provides free REST access to bibliographic metadata for over 140 million scholarly articles, books, and conference papers indexed by DOI. Use it to look up citation data, author info, and publication details.

Beginner Tip

No API key is required, but adding your email as a query param (?mailto=you@example.com) puts you in a higher-rate polite pool with faster responses. Use https://api.crossref.org as the base URL, not the GitHub docs link.

Available Data

book title and author
ISBN and publisher
cover image URL
page count
publication date
article title and content

Example Response

JSON Response
{
  "title": "The Great Gatsby",
  "authors": [
    "F. Scott Fitzgerald"
  ],
  "publishedDate": "1925-04-10",
  "pageCount": 218,
  "categories": [
    "Fiction"
  ],
  "imageLinks": {
    "thumbnail": "https://books.google.com/..."
  },
  "averageRating": 4
}

Field Reference

status Always ok on success; indicates the API processed the request without errors
message.items List of matching works; each item is a scholarly publication record
message.items[].DOI Digital Object Identifier uniquely identifying the publication
message.items[].title Array containing the publication title string or strings
message.items[].author List of author objects with given and family name fields
message.total-results Total count of works matching the search query across all pages

Implementation Example

Request
const url = "https://github.com/CrossRef/rest-api-doc";
const response = await fetch(url);
if (!response.ok) throw new Error(`Request failed: ${response.status}`);
const data = await response.json();
console.log(data);

What Can You Build?

Note: These code examples are AI-generated and unverified. Always refer to the official API documentation for accurate usage.

Common Errors & Troubleshooting

429 Too Many Requests Hitting the anonymous rate limit without identifying yourself
Add '&mailto=your@email.com' to your query string to join the polite pool with a much higher rate limit
Empty items array Search query has no matching results or contains special characters that break the query
URL-encode your query string; test with a known DOI like /works/10.1037/0003-066X.59.1.29 to confirm connectivity
Slow response on broad queries Large result sets without pagination filters
Always add 'rows=10' and 'offset=0' query parameters to paginate and limit response size

Measured Score Breakdown

Live HTTP request to the API endpoint

Reachability 30/30
Speed 10/20
Security 15/15
Developer XP 20/20
Reliability 15/15
Endpoint Response Time 705ms

Fully tested on Jul 23, 2026

Technical Specifications

Auth No Auth
HTTPS REQUIRED
CORS UNKNOWN
Category Books
Difficulty Beginner
Verified: 2026-04-04

Related Tags

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