Choosing a book trim size

Trim size is the width and height of a printed book. Novels are typically something like 5 x 8 and 6 x 9 inches, non-fiction 6 x 9 or 7 x 10, and workbooks 8 x 10 or 8.5 x 11.

But if I was to hand you a book and ask you to show me the book trim size, would you even know which part to show me?

Book trim size is one of those obvious sounding phrases that you'll come across when thinking about book printing. But although it may sound obvious, sometimes it's the obvious things that hold the most potential for error. We think we must already know, so we don't ask. Never fear, though: we're here to help.

What is a book trim size?

The trim size of your book corresponds to the size of your book's pages. To put it another way, when someone prints your book, the trim size is the size that they'll cut your pages to before they bind them together.

It's a tricky thing to change further down the line because, as a measurement, it determines just about everything else. The physical size of your pages will affect what fits onto each page, the number of pages, the printed size of any photos or illustrations, and ultimately your printing costs. Picking the right book trim size, then, is essential. It will change not only how your book looks and feels in your hands, it will also change how much it costs to make. See? We told you it was important.

Let's look at common trim sizes

It's a good idea to know what book trim sizes are considered "popular" for different book types.

Novels often sit around 5 x 8, 5.5 x 8.5 or 6 x 9 inches. These tend to range from smaller to larger trim sizes as the word count increases. The longer the book, the slightly larger the trim. This helps the book from becoming too bulky.

Nonfiction books commonly use 6 x 9, 7 x 10 or larger formats. Books with sidebars, pull quotes, diagrams or tab navigation sometimes suit a slightly wider page. Workbooks and manuals often need larger pages such as 8 x 10 or 8.5 x 11, while children's books, photography books and heavily illustrated titles vary much more. Square and landscape formats can work brilliantly where the images are doing most of the talking.

Look at other books

Pull out a book of a similar genre to your book from a bookshelf, library or local bookshop. See how each size looks and feels in your hands. Does it look right? Is there too much or too little content on a page? Can your eyes easily follow the text from line to line?

Get a ruler and measure the size of the inside pages. Do your thumbs get in the way of the words when you hold it open? How much of each page gets lost into the binding? Then put the book back on the shelf. Does its size make it stand out, or blend in? Large landscape books, for example, can be awkward to shelve.

Imagine someone using your book

A children's book shouldn't be too heavy for a child to lift. But if it's intended for parents to read to their kids, then larger pages may stay open more easily when held in larger hands. If your book is destined for an older audience, then a larger trim size will lend itself better to larger type. However, readers may find a very thick, heavy book too daunting to start in the first place.

A large book of poetry would give a nice airy, open feel to the content, but it is likely to feel much less intimate to read when curled up on the sofa. With each example, it all becomes a question of balance: weighing up pros and cons.

One of your biggest gifts as an author is your imagination, so use it. Think about your book: who will read it, where they might read it, and what size book might fit the scene you're imagining.

Find out what your printer offers

If you're using a print-on-demand service such as Amazon KDP or Ingram, your trim size needs to come from the sizes available for the way your particular book is being produced.

There is plenty of choice, but not every trim size works with every binding, paper type or interior option. Landscape and unusual formats can be more limited, and the options available may also depend on whether you're printing in grayscale or color. Yes, I'm afraid that will mean some more careful thinking, so give yourself time.

Offset printing gives you much more freedom and can accommodate custom sizes, although sticking reasonably close to established book formats is often still the most practical choice.

Think about production costs

Bigger pages mean fewer pages, which means cheaper print costs, right? Not necessarily, we're afraid. Authors on a tight budget will sometimes go for a larger trim size thinking it will shave a few pages off the total page count.

Our advice here is that you should never decide on your trim size based on hoped for cost savings. For example, squashing content onto fewer pages by using a tiny font won't make a significant difference to the per unit cost. However, it could totally wreck the reading experience. In the long run, it will always be more cost effective for you to select the trim size that works best for your content.

So which trim size should you choose?

It's a lot to think about, but trust us, it's worth it. You've looked at common book trim sizes and thought about how your book might fit alongside similar books. You've imagined how your readers would use your book and how it might feel to read. You've also considered the options offered by your printer and the impact of trim size on cost and other printing decisions.

Visit our book formatting services page and select the option most suitable for your book. And if you conclude that more than one trim size could work? Have a chat with your book designer. That's what we're here for.