Amazon KDP Book Sizes Cheat Sheet (Low & Medium Content Books)

If you've ever stared at the KDP dashboard trying to figure out which trim size to pick, you're not alone. 

Getting your book size wrong can mean your interior file gets rejected, your margins look off, or your cover doesn't line up correctly. 

Believe me when I tell you, that getting book cover rejections can be incredibly frustrating.

The most commonly recommended Amazon KDP book sizes are 6 x 9 inches for journals and notebooks, 8.5 x 11 inches for puzzle books and activity books, and 8.5 x 8.5 inches for children's books. Choosing the right trim size from the start saves you time, avoids formatting headaches, and makes your book look professional.

This cheat sheet breaks down the best KDP book sizes by book type so you can get it right the first time.

Why Book Size Matters on Amazon KDP

Before we get into the sizes, here's why this decision matters more than most people realize:

Your trim size affects everything!

It affects your interior template dimensions, your cover file size, your printing costs, and ultimately your royalties (aka the money you make from Amazon)

A book that has a lot of interior pages costs more to print, and eats into your profit margins.

On the other hand, a book that doesn't have enough pages can sometimes lead to dissatisfied customer's that leave you negative reviews.

Getting this right from day one means less time reformatting and more time publishing.

And if you're just getting started, check out 200+ Low Content Book Ideas to help you decide what kind of book to create first. After reading the post, be sure to check back here to pick the right size for your book.

Amazon KDP Book Sizes by Book Type

Here's a quick reference breakdown of the most popular trim sizes and which book types they work best for.

Journals & Notebooks

Recommended size for journals: 6 x 9 inches. This is the go-to trim size for most journal publishers on KDP. It's what buyers expect, it's comfortable to write in, and it keeps your printing costs reasonable.

Puzzle Books & Activity Books

Recommended size for puzzle and activity books: 8.5 x 11 inches. The larger format gives your puzzles plenty of breathing room and makes them much easier for your readers to actually use. This is especially important for large print puzzle books where readability is everything.

If you're thinking about publishing a puzzle book, the Puzzle Book Jumpstart Kit includes done-for-you templates already set up at the right dimensions so that you can skip the formatting issues.

Children's Books

Recommended size for children's books: 8.5 x 8.5 inches. The square format is immediately recognizable as a children's book and photographs beautifully for your Amazon listing images.

Notebooks & Composition Books

Recommended size for notebooks: 8.5 X 11 inches is the most commonly used notebook size on Amazon.

Coloring Books

Recommended size for coloring books: 8.5 x 11 inches. The larger format is what most coloring book buyers expect and gives your illustrations room to shine.

Quick Reference Cheat Sheet

Here's everything in one place so you can bookmark this and come back to it whenever you need it:

A Few Things to Keep in Mind

Before you finalize your trim size, here are a few things worth knowing:

• Printing costs vary by size. Larger books cost more to print which means lower royalties per sale. Always check your royalty estimate in the KDP dashboard before you publish.
  
  
• Your interior template must match your trim size exactly. If you're designing in Canva, set your custom dimensions to match your chosen trim size before you start designing.
  
  
• Bleed vs no bleed matters for covers. If your cover design goes all the way to the edge of the page you'll need to set up bleed. KDP provides a cover template calculator to help with this.
  
  
• Stick to KDP supported trim sizes. Not every size is available — always cross check your chosen dimensions against the full list of supported trim sizes on the KDP help pages before you start designing.

For more on what types of books are worth publishing right now, check out the Best KDP Niches for 2026 and Are Low Content Books Still Profitable?

Ready to Publish Your First Book?

Now that you know exactly which size to use, the next step is getting your first book designed and published. If you want to skip the guesswork on niches, templates, and formatting — my Jumpstart Kits make this process easier for you.

Publishing a gratitude journal? The Gratitude Journal Jumpstart Kit includes done-for-you templates already set up at the right dimensions, profitable pre-researched niches, and a step-by-step guide to get your journal live fast. Grab the Gratitude Journal Jumpstart Kit for $7

Publishing a puzzle or activity book? The Puzzle Book Jumpstart Kit includes everything you need to publish your first puzzle book — profitable niches already researched, templates set up at the correct dimensions, and a clear roadmap to follow. Grab the Puzzle Book Jumpstart Kit for $7

Final Thoughts

Getting your KDP book size right from the start is one of the easiest ways to save yourself time and avoid formatting frustration.

Use this cheat sheet as your go-to reference every time you start a new book and you'll never have to second guess it again.

Bookmark this page, pin it for later, and share it with anyone in your KDP community who's just getting started.

Thanks for reading and Happy publishing!

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