An ISBN is required only for books sold through retail channels, not for copyright. You need a separate ISBN for each format and new edition. In the US, buy from Bowker, the official distributor. Bulk purchases cost less per number.
Chapters
Here's everything you need to know about ISBN numbers in less than 60 seconds. All right, first off, the ISBN is different than a copyright. The ISBN number is the number you see in the barcode, so you only need it if you were selling books retail. Next, you need an ISBN number for each version of your book. So if you have a paperback, a hardback, and an ebook, then you need 3. You also need more ISBNs if you, uh, for if you do a new edition of the same book. Now, if you make some grammatical changes, if you're a self-publisher, you upload a new copy, you don't need a new ISBN number. But if it's a new edition of book, then yes, you do. Now, it's important to know that once the ISBN number is associated with that book, it is permanent forever. Okay, where do you buy ISBNs in the United States? It's Bowker. They're official distributor of ISBNs. Now, you can buy them from a third party, even Amazon IngramSpark you can buy from, but with Amazon, make sure you're buying an ISBN from Bowker. Um, most likely you're not, you're buying an Amazon identification number, so don't do that. The more of them you buy in bulk, the cheaper it gets. Okay.
