What is the Random ISBN Generator?
The International Standard Book Number (ISBN) identifies books and similar publications. Since 2007 the standard form has 13 digits, starting with the prefix 978 or 979. This generator creates random ISBN-13 numbers with either prefix and a correctly calculated final check digit, so they pass the validation used by catalog software, e-commerce platforms and barcode tools.
The check digit is found by multiplying the first twelve digits alternately by 1 and 3, adding the results and choosing the digit that brings the total up to the next multiple of 10. With the Hyphenate option on, numbers are shown in a readable grouped style such as 978-0-1932-1860-4; turn it off to get thirteen plain digits for databases and imports.
You can create up to 100 ISBNs per click and export them as CSV, JSON or TXT. The numbers are random, so they are not assigned to real titles — which makes them safe placeholders for testing, demos and design work.
How to use the Random ISBN Generator
- Set How many? to any number from 1 to 100.
- Leave Hyphenate on for readable numbers, or turn it off for plain digits.
- Press Generate to create your ISBNs.
- Copy them or export the list as CSV, JSON or TXT.
Popular uses
- Developers — test ISBN fields, validators and barcode rendering.
- Library & bookstore systems — fill staging catalogs with realistic identifiers.
- Designers — add believable ISBNs to book cover and back-page mockups.
- Teachers — show how check digits catch errors in everyday numbers.
Why use RandNow?
- Instant & unlimited — no sign-up, no daily caps.
- Private by design — results are generated in your browser, not on our servers.
- Export-ready — copy, CSV, JSON and TXT downloads built in.
- Cryptographically random — powered by the Web Crypto API.
ISBN-13 and the EAN barcode
An ISBN-13 is also a valid EAN-13 barcode number: the 978 and 979 prefixes form a “Bookland” range reserved for publications. That is why the barcode on the back of a book scans at any store checkout and uses the same check digit rule as other retail products.
Real ISBNs are issued by national ISBN agencies to publishers. Generated numbers are not registered, so use them only for testing, mockups and teaching — never on a book you publish. Press Generate again for a fresh set — it’s free and unlimited.
Frequently asked questions
Are these ISBNs real?
They have a valid ISBN-13 format and check digit, but they are random and not assigned to any book.
Does it generate ISBN-10?
No, the tool creates the current 13-digit format with a 978 or 979 prefix.
Can I remove the hyphens?
Yes. Turn off the Hyphenate option to get each ISBN as 13 plain digits.
Can I use a generated ISBN for my own book?
No. Publishers must get real ISBNs from their national ISBN agency; generated numbers are for testing only.