Regular Expressions Cookbook

4.13. Validate ISBNs

Problem

You need to check the validity of an International Standard Book Number (ISBN), which can be in either the older ISBN-10 or the current ISBN-13 format. You want to allow a leading ISBN identifier, and ISBN parts can optionally be separated by hyphens or spaces. ISBN 978-0-596-52068-7, ISBN-13: 978-0-596-52068-7, 978 0 596 52068 7, 9780596520687, ISBN-10 0-596-52068-9, and 0-596-52068-9 are all examples of valid input.

Solution

You cannot validate an ISBN using a regex alone, because the last digit is computed using a checksum algorithm. The regular expressions in this section validate the format of an ISBN, whereas the subsequent code examples include a validity check for the final digit.

Regular expressions

ISBN-10:

^(?:ISBN(?:-10)?:?●)?(?=[-0-9X●]{13}$|[0-9X]{10}$)[0-9]{1,5}[-●]?↵
(?:[0-9]+[-●]?){2}[0-9X]$

Regex options: None

Regex flavors: .NET, Java, JavaScript, PCRE, Perl, Python, Ruby

ISBN-13:

^(?:ISBN(?:-13)?:?●)?(?=[-0-9●]{17}$|[0-9]{13}$)97[89][-●]?[0-9]{1,5}↵
[-●]?(?:[0-9]+[-●]?){2}[0-9]$

Regex options: None

Regex flavors: .NET, Java, JavaScript, PCRE, Perl, Python, Ruby

ISBN-10 or ISBN-13:

^(?:ISBN(?:-1[03])?:?●)?(?=[-0-9●]{17}$|[-0-9X●]{13}$|[0-9X]{10}$)↵
(?:97[89][-●]?)?[0-9]{1,5}[-●]?(?:[0-9]+[-●]?){2}[0-9X]$

Regex options: None

Regex flavors: .NET, Java, JavaScript, PCRE, Perl, Python, Ruby

JavaScript

// `regex` checks for ISBN-10 or ISBN-13 format var regex = /^(?:ISBN(?:-1[03])?:? )?(?=[-0-9 ]{17}$|[-0-9X ]{13}$|↵ [0-9X]{10}$)(?:97[89][- ]?)?[0-9]{1,5}[- ...