Google Books

Overview

The Google Books API lets you search the Google Books corpus — millions of scanned books — and fetch volume metadata: titles, authors, covers, descriptions, ISBNs, page counts, and (where available) preview/read links. Keyless for basic search; OAuth for user bookshelves and reading positions.

Note (verified 2026-08): the keyless search quota is heavily shared — bursts return HTTP 429. Register a free API key from Google Cloud Console to get your own quota.

Quick Start

Search volumes (keyless, verified live but rate-limited):

curl "https://www.googleapis.com/books/v1/volumes?q=harry+potter&maxResults=5"

Get a volume by ID:

curl "https://www.googleapis.com/books/v1/volumes/zyTCAlFPjgYC"

With a key (recommended):

curl "https://www.googleapis.com/books/v1/volumes?q=subject:science&key=YOUR_KEY"

What’s in a volume

volumeInfo: title, authors, publisher, publishedDate, description, pageCount, categories, averageRating, imageLinks (thumbnail), industryIdentifiers (ISBN-10/13), previewLink, infoLink.

Authentication

• Keyless: basic search works without a key (shared quota, 429 under load).
• API key: free from Google Cloud Console (enable Books API) — your own quota.
• OAuth: for user-scoped features (bookshelves, reading positions) — the listing’s OAuth refers to this.

Rate Limits & Notes

• Keyless quota is small and shared; get a key for anything real.
• q supports fielded queries: intitle:, inauthor:, isbn:, subject:, inpublisher:.
• country parameter affects availability of preview/read links.
• Search results include accessInfo (viewability, PDF/EPUB availability).

FAQ

Is Google Books API free? Yes — keyless search works; a free API key gives you a personal quota.

Why do I get 429 without a key? The anonymous quota is shared across all users — register a key.

Can I read full books through it? Only where publishers allow preview/embedding — the API returns what Google Books can show.