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keyronne.com api book
https://keyronne.com/api/book
payable
Look up a book by ISBN (10 or 13 digit): title, subtitle, authors, publishers, publish date, page count, subjects, and cover image. Validates the ISBN check digit first (rejecting typos unpaid) and returns both ISBN forms. Data from Open Library; attributed in every response. POST a JSON body like: {"isbn":"9780140328721"}
We sent a real
POST request to this endpoint and it
answered 402 with payment requirements we could parse.
- Price
- $0.004
- Network
- base
- Pay to
- 0xB86F95EF5FA904318Ea9Df3b59AdCe099b478fC4
- Spec dialect
- v2 (declares x402Version 2)
- Transport
- PAYMENT-REQUIRED header
- HTTP method
- POST
- Response latency
- 10 ms
- Payment options
- 1 usable of 1
- Last checked
- 2026-08-10T09:09:06.874Z (4d ago)
- Category
- media
Re-check it yourself:
curl "https://api.the402.dev/validate?url=https%3A%2F%2Fkeyronne.com%2Fapi%2Fbook"