Open Library

About Open Library

Open Library provides a set of APIs for looking up and searching bibliographic data, including book search, search-inside-book text search, cover images, work and edition records, author records, subject-based book lists, user reading lists, and recent changes across the catalog. Data is available in JSON, YAML, and RDF/XML formats, and structured data for most items can be retrieved by appending a file extension to an Open Library page URL.

Access is rate-limited to 1 request per second for unidentified requests and 3 requests per second for requests that include a User-Agent header with an application name and contact email. The APIs are intended for open-source and mission-aligned projects, library and education tools, and real-time, low-volume, human-facing discovery services rather than bulk data retrieval or high-traffic commercial backends; bulk access is available separately through monthly data dumps.

The service is used by organizations and developers including Trove (National Library of Australia), the library systems Koha and Evergreen, the Library of Congress's read.gov, and various third-party plugins and applications such as an OpenBook WordPress plug-in and reading-list apps.

Key features

• Book Search API for finding books, authors, and more
• Search inside API for full-text search within millions of books
• Covers API to fetch book covers by ISBN or Open Library identifier
• Lists API for creating, reading, and modifying user reading lists
• Structured bibliographic data available in JSON, YAML, and RDF/XML formats
• Bulk data available via free monthly data dumps

Frequently asked questions