BYTETOOLS

Gutendex (Project Gutenberg) API

Free Project Gutenberg API with no key: search 75,000+ public domain ebooks with authors, subjects, download links and full text in multiple formats. Tested.

No API key requiredCORS enabledHTTPSFree tier

Endpoint tested and returned HTTP 200 on 2026-08-20

What is the Gutendex (Project Gutenberg) API?

Gutendex is a free, key-free API for searching Project Gutenberg's catalogue of more than 75,000 public domain ebooks, returning author, subject, language, download counts and direct links to the full text in several formats.

Project Gutenberg hosts the largest collection of free public domain ebooks, but its own site is awkward to query programmatically. Gutendex wraps the catalogue in a clean JSON API with proper search and filtering.

The `formats` object is the practical payoff: each book links directly to plain text, EPUB, HTML and Kindle versions. Because everything is public domain, you can download, redistribute and build on the full text without any licensing concern.

Quick facts

Base URL
https://gutendex.com
Authentication
No API key required.
Rate limit
No published hard limit; fair use expected.
Pricing
Free. All books are public domain.
CORS
Enabled — callable directly from browser JavaScript
Official docs
Read the docs

How to use the Gutendex (Project Gutenberg) API

Every request below was executed against the live API on 2026-08-20, and the response shown is the real body it returned — not an illustration.

1. Search public domain ebooks

GET https://gutendex.com/books/?search=austen

curl
curl 'https://gutendex.com/books/?search=austen'
JavaScript (fetch)
const res = await fetch("https://gutendex.com/books/?search=austen");
if (!res.ok) throw new Error(`Request failed: ${res.status}`);
const data = await res.json();
console.log(data);
Python (requests)
import requests

res = requests.get("https://gutendex.com/books/?search=austen", timeout=20)
res.raise_for_status()
print(res.json())
Response — HTTP 200 (truncated)
{
  "count": 49,
  "next": "https://gutendex.com/books/?page=2&search=austen",
  "previous": null,
  "results": [
    {
      "id": 1342,
      "title": "Pride and Prejudice",
      "authors": [
        {
          "name": "Austen, Jane",
          "birth_year": 1775,
          "death_year": 1817
        }
      ],
      "summaries": [
        "\"Pride and Prejudice\" by Jane Austen is a novel published in 1813. It follows Elizabeth Bennet, who must learn to see past first impressions and hasty judgments. With five daughters and an estate that can only pass to male heirs, the Bennet family faces financial pressure to marry well. When wealthy Mr. Darcy arrives in their countryside neighborhood, his pride and Elizabeth's prejudice set the stage for misunderstandings, hidden truths, and unexpected revelations about character and love. (This is an automatically generated summary.)"
      ],
      "editors": [],
      "translators": [],
      "subjects": [
        "Courtship -- Fiction",
        "Domestic fiction",
        "England -- Fiction",
        "Love stories",
        "Sisters -- Fiction",
        "Social classes -- Fiction",
        "Young women -- Fiction"
      ],
      "bookshelves": [
        "Best Books Ever Listings",
        "Category: British Literature",
        "Category: Classics of Literature",
        "Category: Novels",
        "Category: Romance",
        "Harvard Classics"
      ],
      "languages": [
        "en"
      ],
      "copyright": false,
      "media_type": "Text",
      "formats": {
        "text/html": "https://www.gutenberg.org/ebooks/1342

Parameters

ParameterTypeRequiredDescription
books/pathOptionalBook search and listing. books/
searchstringOptionalSearch author and title. austen
languagesstringOptionalComma-separated language codes. en,fr
topicstringOptionalSearch subjects and bookshelves. adventure
sortstringOptionalpopular, ascending or descending. popular
pageintegerOptionalPage number. 2

Response fields

countinteger
Total books matching the query.
next / previousstring
Pagination URLs.
results[].idinteger
Project Gutenberg book id.
results[].titlestring
Book title.
results[].authorsarray
Authors with birth and death years.
results[].subjectsarray
Library subject classifications.
results[].formatsobject
Direct download URLs by MIME type — text, EPUB, HTML, Kindle.
results[].download_countinteger
Popularity signal.

What you can build with the Gutendex (Project Gutenberg) API

  • Build a public domain ebook reader or library
  • Source full text for natural language processing
  • Create a classic literature discovery site
  • Provide free reading material in an education app

Common errors and how to fix them

Empty results

The search matched nothing.

Fix: Search covers author and title only; use `topic` to search subjects and bookshelves.

Choosing a format

The formats object is keyed by MIME type.

Fix: Look for 'text/plain; charset=utf-8' for raw text, or 'application/epub+zip' for EPUB.

Slow responses under load

It is a free community service.

Fix: Cache results; the catalogue changes rarely.

Gutendex (Project Gutenberg) API — frequently asked questions

Is Gutendex free?

Yes, completely free with no API key. Every book it indexes is public domain.

Can I download the full text?

Yes. The `formats` object links directly to plain text, EPUB, HTML and Kindle versions, and public domain status means you can redistribute them freely.

How many books are available?

More than 75,000 titles from Project Gutenberg, across many languages though predominantly English.

How do I search by genre?

Use the `topic` parameter, which searches subjects and bookshelves. The `search` parameter only covers author and title.

Tools that pair with this API

Gutendex (Project Gutenberg) is an independent third-party service and is not affiliated with ByteTools or ByteVancer. Details on this page were verified on 2026-08-20; always check the official documentation before relying on this API in production, as terms and limits can change.