What Size Should Your Book Be? Understanding Book Trim on Amazon KDP

When you’re focused on the writing process, it’s not often you’re thinking about the more technical aspects of self-publishing, but as you get closer to the finish line, one decision you’ll need to make is determining the trim size of your book.

Whether you’re working on a novel, a work of nonfiction, or a journal, the size of your book can significantly impact not only its appearance but also its distribution, cost, and ultimately, your profits. (Which is part of the reason we publish the books, right?)

Today we’re going to talk about how to choose the right size for your self-published book.

Understanding Standard “Trim” Sizes

What is “Trim” anyway? In book publishing, the term "trim" refers to the final size of a book after it has been printed, bound, and the edges have been cut to the specified dimensions. The trim size is the book's physical dimensions, such as 6" x 9" or 5.5" x 8.5", which are common sizes for trade paperbacks.

Choosing the right trim size is important because it affects the book's overall appearance, layout, and how it will be displayed on shelves. It also influences aspects like page count and production costs.

The most common sizes for paperback books include:

5.5" x 8.5": This is perhaps the most standard size for paperback books, especially for novels and nonfiction. It’s a versatile option that’s easy to handle and commonly used by both indie authors and traditional publishers.
5" x 8": A slightly smaller alternative, this size is often referred to as "airport size" and is typically used for thicker books published by big houses. While it’s a familiar format, it’s not as recommended for self-publishers due to potential limitations in distribution.
6" x 9": Another standard size, this option gives your book a bit more presence. The extra half-inch around the perimeter makes the book feel more substantial and professional.

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Okay, So… Why Does Trim Size Matter, Anyway?

Your book’s trim size can affect several aspects of the publishing process, including:

Distribution: Certain trim sizes are better suited for expanded distribution programs, especially if you’re using platforms like Amazon KDP or IngramSpark. For example, opting for a non-standard size like a square format may limit your distribution opportunities, particularly in brick-and-mortar stores.
Print Cost and Royalties: The size of your book directly influences the print cost. A larger trim size often means fewer pages, which can lower your printing costs. Conversely, a smaller size with more pages increases the print cost, potentially reducing your royalties unless you raise your book's price.
Reader Experience: Consider your target audience when choosing your trim size. For instance, if your book is likely to be read by an older demographic, you might want to avoid making the text too small. A larger trim size can accommodate bigger text without making the book too thick.

The Impact of Text Size and Spine Thickness

The relationship between trim size, text size, and spine thickness is crucial. A smaller trim size with smaller text can result in a thinner spine, which might make your book feel less substantial. On the other hand, increasing the trim size or text size can make your book thicker and more visually appealing, but it will also increase print costs.

For example, if your manuscript is 100,000 words, you might want to consider a 6" x 9" trim size with smaller text to avoid making the book excessively thick. If your manuscript is shorter, say 20,000 to 30,000 words, a 5.5" x 8.5" size with slightly larger text might be more appropriate.

Matte vs. Glossy Finish: Which to Choose?

The finish of your book cover is another important decision. The two most common options are matte and glossy:

Matte Finish: Offers a velvety, luxurious feel and is increasingly popular for its modern look. However, if your cover features a lot of dark colors, matte can show fingerprints more easily.
Glossy Finish: Provides a polished, shiny look that’s more traditional. It’s less prone to showing fingerprints and can make your cover art pop, but it may not feel as high-end as matte.

Fortunately, the finish can be changed even after your book is published, unlike the title, subtitle, or ISBN. So if you’re unsure, you can always start with one finish and switch later if needed.

Choosing the Right Size for Journals and Workbooks

If you’re creating a journal or workbook, the two most common sizes are:

7.5" x 9.25"
8" x 10"

These sizes are perfect for providing enough space for writing and working through exercises. The larger size, similar to printer paper, offers a more comfortable writing experience, while the slightly smaller option is more portable and easier to carry around.

Ultimately, the trim size you choose should reflect the nature of your book and the experience you want to create for your readers. Consider the print cost, distribution options, and the overall look and feel you want to achieve. By making informed decisions about these elements, you can maximize your profit margins without sacrificing the quality of your book.

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