I ask ChatGPT about ISBNs, and respond to its response.
What ChatGPT Says:
An ISBN (International Standard Book Number) is a unique numerical identifier assigned to every book published. ISBNs are used to identify, track, and order books, and are a requirement for books to be sold through traditional bookstores and online retailers.
In self-publishing, ISBNs can be purchased by the author or publisher and assigned to their books. ISBNs are used to track sales and royalties, and also help increase the visibility of a book by making it more discoverable through online retailers and bookstores.
ISBNs are issued by national ISBN agencies, and self-publishing authors can purchase ISBNs from their local ISBN agency. In some countries, such as the US, self-publishing platforms like Amazon Kindle Direct Publishing and IngramSpark provide ISBNs for their authors, but in most countries the author or publisher is responsible for obtaining an ISBN.
It’s important to note that an ISBN is required for a physical book, but not necessary for an ebook, since they can be tracked through other means. However, including an ISBN can increase the discoverability and professionalism of the ebook.
It’s important to note that ISBNs are unique to each edition and format of a book, so if you are publishing a hardcover, paperback, and ebook version of your book, each version will need its own ISBN.
What Anna Says:
This is a good summary. ISBNs are purchased from the country where it is published. To find your local ISBN agency, you can google “ISBN country”. For Australia, the agency is called Thorpe-Bowker.
I had three ISBNs for each novella: ebook, paperback, and audiobook.
Note that you need to fill in the details on the local ISBN agency website once you have published. Information you need to fill in includes the price and format.
ISBNs are not transferrable once purchased. Beware of purchasing ISBNs from someone else. There are limited exceptions, like Amazon KDP and IngramSpark, but the ISBNs remain the property of those organisations and come with terms and conditions. One example is that you can’t use the Amazon KDP ISBN on another platform.