ISBN vs ASIN

What it means

Both numbers identify a book, but for different people.

• ISBN: the book trade’s number. Shops, distributors and libraries everywhere use it. Each format of a book has its own: the paperback, the hardcover and the EPUB each get one. Since 2007 ISBNs have 13 digits. You get them from the ISBN agency in your country.
• ASIN: Amazon’s number. Amazon gives one to everything in its catalog. Only Amazon uses it.

A cozy mystery on Kindle, Kobo and in paperback might have an ASIN for the Kindle ebook, an ISBN for the paperback, and perhaps a second ISBN for the ebook sold through other stores. A how-to guide sold only as a Kindle ebook might have just an ASIN.

Why it matters when you sell direct

For ebooks on your own store, you need neither. KDP does not need an ISBN for ebooks, and no store but Amazon reads an ASIN.

For print, the ISBN matters. KDP asks for one on paperbacks and hardcovers, bookstores order by it, and libraries catalog by it. If you sell your paperback direct as well, use the same ISBN so it is clearly the same book.

How Lanternbee handles it

Each edition in Lanternbee can carry its own ISBN, and Lanternbee checks it is valid. Lanternbee has no use for ASINs. Readers can still send their ebooks to their Kindle with send-to-Kindle.