Quick guide
Try an example
You enter
- ISBN
0-306-40615-2
You get
- Checksum
Valid
- Normalized ISBN
0306406152
How it works and limits
Spaces and hyphens are accepted. ISBN-10 may end in X. The result checks the code and does not look up a book.
Check the format and check digit of an ISBN-10 or ISBN-13.
Text Stateless0-306-40615-2
Valid
0306406152
Spaces and hyphens are accepted. ISBN-10 may end in X. The result checks the code and does not look up a book.