Open Library ISBN Lookup

Look up any book by ISBN against the Internet Archive's free, open Open Library catalog — title, subtitle, authors, publishers, publish date, page count, subjects, a cover image URL, and an excerpt where available. No API key, no scraping — this hits the official public Open Library API directly.

Features

• ISBN → full book record. Title, subtitle, and every listed author and publisher.
• Physical & catalog detail. Publish date, page count, and up to 15 subject tags.
• Cover & excerpt. A direct cover image URL and, where Open Library has one, a text excerpt.
• Pay only for hits. ISBNs that don't resolve to a catalog record cost nothing — see Pricing.
• Built for bulk. Feed in thousands of ISBNs; concurrency, keyword filtering, and column selection are all configurable.

How to use Open Library ISBN Lookup — Free Book Metadata API

1. In the Apify Console. Open the actor page and click Start — the isbns field is already pre-filled with a working example. Results land in the run's dataset as soon as each item is found.
2. Via the API. Call it directly with a POST request — no Console needed once you have an API token:

   curl "https://api.apify.com/v2/acts/accountable_eel~openlibrary-isbn-lookup/run-sync-get-dataset-items?token=<YOUR_TOKEN>" \
     -X POST \
     -H "Content-Type: application/json" \
     -d '{"isbns":["9780140328721"]}'
   

3. On a schedule. Save this actor as an Apify Task with the input you want, then add a Schedule (hourly, daily, weekly) so it runs on its own — no server of your own required.

Input

{
  "isbns": [
    "9780140328721"
  ]
}

One ISBN-10 or ISBN-13 per line (spaces and dashes are fine). Accepted formats: 9780140328721, 0-14-032872-1.

{
  "isbns": ["9780140328721", "0-14-032872-1"],
  "testRun": false,
  "onlyFound": false,
  "maxConcurrency": 5
}

isbns is a list of ISBN-10 or ISBN-13 numbers — spaces and dashes are fine, they're stripped automatically. testRun limits a run to the first 5 items so you can check your input before spending on the full list. onlyFound hides rows where nothing was found (misses are always free regardless). Optional includeKeywords/excludeKeywords filter results by keyword, and maxResults stops the run early once that many results have been found. columns lets you pick which fields to include (all are on by default). maxConcurrency (default 5, max 20) caps parallel requests.

Output

query	found	status	title	isbn	subtitle	authors	publishers	publishDate	numberOfPages	subjects	coverUrl	openLibraryUrl	excerpt	scrapedAt
9780140328721	true	OK	Fantastic Mr. Fox	9780140328721		["Roald Dahl"]	["Puffin"]	October 1, 1988	96	["Animals","Hunger","Open Library Staff Picks","Juvenile fiction","Children's stories, English","Foxes","Fiction","Zorros","Ficción juvenil","Tunnels","Interviews","Farmers","Children's stories","Rats","Welsh Authors"]	https://covers.openlibrary.org/b/id/15152634-L.jpg	http://openlibrary.org/books/OL7353617M/Fantastic_Mr._Fox	Down in the valley there were three farms.	2026-08-23T21:05:07.226Z

One row per ISBN, for example:

{
  "query": "9780140328721",
  "found": true,
  "status": "OK",
  "isbn": "9780140328721",
  "title": "Matilda",
  "subtitle": null,
  "authors": ["Roald Dahl"],
  "publishers": ["Puffin Books"],
  "publishDate": "1998",
  "numberOfPages": 240,
  "subjects": ["Fiction", "Children's stories", "Family life"],
  "coverUrl": "https://covers.openlibrary.org/b/id/8231856-L.jpg",
  "openLibraryUrl": "https://openlibrary.org/books/OL21524582M/Matilda",
  "excerpt": null,
  "scrapedAt": "2026-08-21T12:00:00.000Z"
}

An ISBN with no matching Open Library record comes back as "found": false with status: "NOT_FOUND" (or "BAD_FORMAT" if it isn't a valid ISBN-10/13 shape to begin with) and a plain-English message — these rows are never charged.

Use cases

• Library/catalog enrichment. Bulk-fill title, author, and subject metadata for a collection known only by ISBN.
• Bookstore & marketplace listings. Auto-populate cover image, publisher, and page count for book listings.
• Reading-list building. Turn a plain ISBN list into a formatted bibliography with authors and publish dates.
• Data cleaning. Backfill missing book metadata in a dataset that only has ISBNs.
• Content moderation research. Pull subject tags to categorize a large set of books by theme.

Pricing

$4 per 1,000 ISBNs, plus a $0.005 start fee. Misses (found:false) are never charged.

Use it from Clay, n8n, Make, or an AI agent

This actor runs synchronously over plain HTTP — call it directly from a script, a workflow tool, or an AI agent, no Apify Console needed once you have an API token.

curl "https://api.apify.com/v2/acts/accountable_eel~openlibrary-isbn-lookup/run-sync-get-dataset-items?token=<YOUR_TOKEN>" \
  -X POST \
  -H "Content-Type: application/json" \
  -d '{"isbns":["9780140328721"]}'

n8n. Add an HTTP Request node: Method POST, URL https://api.apify.com/v2/acts/accountable_eel~openlibrary-isbn-lookup/run-sync-get-dataset-items?token=<YOUR_TOKEN>, Body Content Type JSON, JSON Body {"isbns":["9780140328721"]} (swap in an expression from an earlier node for a real value).

Clay. Add an "HTTP API" column: Method POST, URL https://api.apify.com/v2/acts/accountable_eel~openlibrary-isbn-lookup/run-sync-get-dataset-items?token=<YOUR_TOKEN>, Body {"isbns":["{{ISBN}}"]}, mapping the row's ISBN into the isbns array.

MCP. In Claude, Cursor, or any MCP client with the Apify MCP server, ask for "Open Library API — ISBN to Book Metadata" — the agent will find and run this actor.

FAQ

What counts as "not found"? An ISBN that isn't in Open Library's catalog comes back as NOT_FOUND. An input that doesn't even match the ISBN-10/13 digit pattern (after stripping spaces and dashes) is flagged BAD_FORMAT before a request is even made — either way, no charge.

Do I need to format the ISBN a specific way? No — spaces and dashes (0-14-032872-1) are stripped automatically before the lookup, so both hyphenated and plain digit strings work.

Does every book have a cover, excerpt, and full subject list? No — Open Library's coverage varies by edition. coverUrl and excerpt are only populated when Open Library has them on file for that specific ISBN; subjects is capped at 15 tags when more are listed.

Which cover image size do I get? The actor requests the largest available cover (cover.large, falling back to cover.medium) so images are usable for display, not just thumbnails.

How fresh is the data? Live — every run queries Open Library's API directly, not a cached snapshot.

What proxy should I use? Apify Proxy is enabled by default; Open Library's public API is generally permissive, but residential proxies are available if you see blocks on large runs.