How to automatically apply ISBN hyphenation?

I've got ISBN numbers (10-digits and 13 digits) without the dashes. Now I'm looking for a way to add those dashes automatically.

I found some useful information here: http://www.isbn.org/standards/home/isbn/international/hyphenation-instructions.asp

But I'm not sure if it's doable at all, because the publisher identifier has a random length, and without knowing it, it's maybe not possible to determine the correct positions for the dashes.

Does anybody know if it's possible somehow?

Thanks a lot!

You can deduce the length of the publisher identifier if you have the full range tables.

Example 1. ISBN 0141439564 (Penguin: Great Expectations)

• The group identifier is 0 (English language).
• The publisher ranges for this group are 00–19, 200–699, 7000–8499, 85000–89999, 900000-949999, and 9500000–9999999
• The next two digits are 14, which is in the range 00–19, so the publisher has 2 digits.
• So the hyphenated form is 0-14-143956-4

Example 2. ISBN 2253004227 (Poche: Germinal)

• The group identifier is 2 (French language)
• The publisher ranges for this group are 00–19, 200–349, 35000–39999, 400–699, 7000–8399, 84000–89999, 900000–949999, 9500000–9999999
• The next three digits are 253, which is in the range 200–349, so the publisher has 3 digits
• So the hyphenated form is 2-253-00422-7

You can check your algorithm at the Library of Congress's ISBN hyphenation tool.