ISBN Validator
Validate International Standard Book Numbers (ISBN). Check both ISBN-10 and ISBN-13 formats with checksum verification.
Enter ISBN
Enter with or without hyphens. ISBN-10 can end with X.
Example ISBNs
- ISBN-10: 0-306-40615-2
- ISBN-10 with X: 0-43-965068-X
- ISBN-13: 978-0-306-40615-7
- ISBN-13 (979): 979-10-90636-07-1
How ISBN Validation Works
ISBN (International Standard Book Number) is a unique identifier for books. There are two formats: ISBN-10 (older) and ISBN-13 (current standard).
ISBN-10 Format (Legacy):
- 10 digits total
- Last digit is a checksum (0-9 or X, where X = 10)
- Checksum calculated using modulo 11 algorithm
- Example: 0-306-40615-2
ISBN-13 Format (Current):
- 13 digits total
- Starts with 978 or 979 (GS1 prefix for books)
- Last digit is a checksum (0-9)
- Checksum calculated using modulo 10 algorithm
- Example: 978-0-306-40615-7
When ISBN is Used:
- Book publishing and distribution
- Library cataloging systems
- Online bookstore inventory
- Book sales tracking and royalties
- ISBN is required for most retail book sales
FAQ
What's the difference between ISBN-10 and ISBN-13?
ISBN-10 is the older 10-digit format, while ISBN-13 is the current 13-digit standard (adopted in 2007). ISBN-13 adds a 978 or 979 prefix. All new books use ISBN-13, but both are still valid.
Can I convert ISBN-10 to ISBN-13?
Yes. Take the 9-digit ISBN-10 (without checksum), add the 978 prefix, then calculate a new checksum using the ISBN-13 algorithm. For example: 0-306-40615-2 becomes 978-0-306-40615-7.
Does validation mean the book exists?
No. This validator only checks if the ISBN format and checksum are mathematically correct. It does NOT verify if the ISBN is registered or if a book with that ISBN exists. Use ISBN databases or bookstore APIs for that.