Books — entry 010 of 22
Gutendex
Gutendex is a free, open-source JSON API — built independently of Project Gutenberg — that wraps its roughly 75,000 public-domain ebooks with searchable, paginated metadata: authors, subjects, bookshelves, languages, and direct links to every available download format from plain text to EPUB and Kindle. No account or key is needed to query it, and the project's own source enables cross-origin requests from any domain rather than restricting them. Anyone needing sustained high-volume traffic is asked to run their own instance of the open-source server instead of hammering the public one.
AuthenticationNone requiredCall it straight away — no key, no signup.
HTTPSSupportedTraffic is encrypted in transit.
CORSEnabledCallable directly from browser JavaScript.
PricingFreeNo paid tier — free for the documented use case.
FormatsJSONResponses can be requested as JSON.
GreatAPIs Score
Score88
Authentication25/25No authentication required
Pricing20/20Free to use
Docs14/20Documentation URL provided
Formats9/15Single response format
Freshness20/20Verified within 6 months
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<a href="https://greatapis.com/api/gutendex/"><img src="https://greatapis.com/badge/gutendex.svg" alt="Scored 88 on greatapis.com"></a>Auth quickstart
- No key needed — call it now.
Stored keyNo key stored
Your key is stored only in this browser (localStorage) and sent directly to the API — never to greatapis.