Free APIs
Free Books & reference APIs
| Free tier | Docs | ||
|---|---|---|---|
Book, author and edition data plus covers
Catch: Identify your app via User-Agent for heavy use | Free, no key | No key | docs |
Search books and volume metadata
Catch: Quota can be raised via Google Cloud console | Free; default daily quota | API key | docs |
| Free, no key | No key | docs | |
Wikipedia, Wiktionary and Commons content and search
Catch: Requires a descriptive User-Agent; rate limited | Free; no key for light use | No key | docs |
Search and fetch archived books, audio, video and web pages
Catch: Be gentle; heavy crawling is blocked | Free, no key for most endpoints | No key | docs |
Library of Congress collections as JSON
Catch: Rate limits apply | Free, no key | No key | docs |
FAQ
What is the best free books & reference API?+
Open Library API, Google Books API, Gutendex are good places to start. Compare the free tiers and catches in the table; they differ mostly in limits and whether commercial use is allowed.
Is there a books & reference API without an API key?+
Yes: Open Library API, Gutendex, Wikimedia REST API, Internet Archive APIs, Library of Congress API work without a key.
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