#library

ISBN validation and conversion as an API, computed locally and deterministically. The validate endpoint detects whether a code is an ISBN-10 or an ISBN-13, ignores hyphens and spaces, and verifies the check digit — ISBN-10 with the mod-11 scheme whose last character may be the letter X (for 10), and ISBN-13 with the weighted 1-3-1-3 mod-10 scheme — so 0-306-40615-2 and 978-0-306-40615-7 both validate while a wrong check digit is rejected. The checkdigit endpoint computes the trailing check digit for a 9-digit ISBN-10 stem or a 12-digit ISBN-13 stem (and recomputes it for a full code). The convert endpoint converts between the two forms: an ISBN-10 becomes an ISBN-13 by prefixing 978 and recomputing the check, and a 978-prefixed ISBN-13 converts back to ISBN-10 (979-prefixed codes have no ISBN-10 equivalent). Everything is computed locally and deterministically, so it is instant and private. Ideal for publishing, library, bookstore, catalogue, e-commerce and metadata app developers, ISBN-validation and barcode tools, and inventory systems. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This is ISBN-specific validation and conversion; for generic Luhn/Verhoeff check digits use a check-digit API.

api.oanor.com/isbn-api

Wikisource as an API — the Wikimedia free digital library of original source texts. Wikisource collects public-domain and freely-licensed primary texts: classic literature, poetry and plays, historical speeches, treaties and constitutions, religious and philosophical works, landmark court decisions, essays, letters and more, faithfully transcribed. This API wraps the official Wikisource MediaWiki service into clean JSON. /v1/search?q=Gettysburg Address searches the library and returns matching work and page titles with a text snippet and word count. /v1/work?title=Gettysburg Address returns a work's metadata — a short description, a text preview, the total character length and the canonical URL. /v1/text?title=Gettysburg Address (Bliss copy) returns the full plain text of a work (rendered and cleaned from the wiki source, capped at 60,000 characters with a truncated flag when longer) — the actual readable document, including transcribed works that template-based pages assemble. Many works are split into sub-pages or exist in several versions, so use /v1/search to find the exact page title first. Ideal for digital-humanities and literature apps, e-reading and quotation tools, NLP corpora of historical texts, and education. Content is public domain or CC BY-SA. Distinct from book-metadata catalogues and encyclopaedias — this is the actual full text of primary sources and classic works. For free textbooks use the Wikibooks API, for the encyclopaedia the Wikipedia API.

api.oanor.com/wikisource-api

Search millions of books, look up editions by ISBN-10/13 and find authors — with covers, publish years, publishers, page counts and subjects. Powered by Open Library (Internet Archive).

api.oanor.com/books-api