Today we will talk briefly about where to put the barcode and how it should look to give your reader the most information about your book easily.
Barcode Placement
One you get an ISBN and a Barcode, you need to know where to put it. It may be tempting to put it in "cute" places around the back cover (or even on the front), but for the most part that should be resisted. Most people and bookstores will expect the barcode to be on the back cover, at the lower right corner. If you are electing to allow your book printer (like KDP) to place your barcode, they will put it in a gap that you leave for it as indicated by a white block, but by default it will go in to lower right corner.
If you do have a good reason to place the barcode somewhere else, you will have to afix it to the back cover as it will be submitted to the printer.
Area Around the Barcode
While the barcode itself is enough for your typical bookstore to sell your book, other information can help both the bookstore and your reader to understand more about your book. Obviously having a good bio and hook on the back cover is ideal, but it is also important to include an easy to read price tag and information about the genre. I like to put my price on the side of the barcode in USD so it can be easily found and I place my suggested categories about the price. This gives your readers a quick look at the type of content that may be in the book.