After my last post, a friend commented on Facebook to point out, “This doesn’t give you an ISBN, just the ability to print a barcode for any ISBN. You have to pay for prefixes for those things…” Well, yeah, I said. I know that. Therefore it hadn’t even occurred to me that the distinction might bear explaining!

So here’s a little primer on ISBNs.

The ISBN is the identification number which is required for most online sales as well as library systems. It stands for International Standard Book Number. (Note that this means “ISBN number”, which I used to hear all the time from my bookstore colleagues in the early 1990s, ranks up there with “ATM machine” as an instance of RAS syndrome.)

Every distinguishable edition of a book (most often, hardcover and paperback, or 1st edition vs. revised/2nd edition) requires a separate, unique ISBN. Exceptions that can retain the same ISBN include (a) reprinting a book, in the same format as previously, with a new cover but the same interior, or (b) reprinting a book, in the same format as previously, with minor text corrections to individual pages but no substantial revisions or additions.

Now ISBNs, as an international standard, can only be issued by the official ISBN Agency for each country. The authorized U.S. ISBN Agency is a private company called R.R. Bowker, LLC, who also used to publish the multi-volume hardcover catalog of Books In Print, which was completely indispensable back before there was an Amazon.com.

Bowker will issue “a publisher” (whether that’s yourself as a private individual, or a corporate entity) a single ISBN, for a service charge of $125 per book. But for $250, you can apply for a “prefix” and reserve a series block of 10 usable ISBNs. Either way, start with the application link here: http://www.isbn.org/standards/home/isbn/us/application.asp

Why the jump from 1 to 10? Because of the way it’s structured. Modern ISBNs have 13 digits, as follows:

• 978 = arbitrary 3-digit prefix added in 2007 to convert all formerly 10-digit ISBN strings to 13 digits
• 0 or 1 = US country code
• The intervening 8 digits are divided up between the publisher prefix and the title identifier. Large publishers have very short prefixes (3 or even 2 digits), because they could easily have 10,000+ distinct titles/editions in their catalog, so they need to be able to encode 5 figures’ worth of unique digit strings under their prefix. The smallest publishers will have a 7-digit prefix, leaving only 1 digit for their title space: 0 through 9. That’s your block of 10. Single-ISBN reservations simply get issued a string of all 8 digits at once and you’re done—you can’t get another in the same sequence after that.
• The last digit = a check digit for redundancy. This is like a parity bit in computer programming: it’s calculated based on the preceding 12 (or formerly 9) digits. This is why the ISBN-13 for a given book shows a different check digit from the old ISBN-10.

Bowker will also sell you a bar code for your ISBN, for the modest additional charge of $25 each. You do, in fact, need a bar code to place on the cover—bookstores, online retailers, and libraries all require it. But as I already noted, that’s the part for which there are now free online generators.

Other important cataloging steps have to be addressed separately from ISBN registration if you want to do them:

• Register for listing in Books in Print (free)
• Copyright deposit (currently $35, although note that copyright per se inheres in your work; this registration basically serves to formalize your claim)
• Cataloging-in-Publication from the Library of Congress (only for publishers who “have already published a minimum of three titles by three different authors [that] have been widely acquired by U.S. libraries”).

Further reading for the truly intrigued: Bowker’s ISBN FAQ list.

Oh, and in case you’re wondering: I’m still waiting on the last text corrections from the author before I can send the book project to press, which is why I have time to write all this. :-)