Book size, also known as trim size, may seem like a trivial detail in your book publishing strategy. But depending on your readers, your genre, and your book type, you probably should take a look at the different options and determine which book size will be best for you.
- What trim size is
- What are the standard book sizes
- What sizes are offered through KDP Print and IngramSpark
- Which you should choose
Table of contents
What is Book Trim Size?
Put simply, trim size is the height and width of your print book. Some books will be larger than others, some smaller.
For those who publish through KDP or IngramSpark, they will present you with a list of possibilities, each with pros and cons, depending on what you want.
Note: In the US, inches are primarily used to denote book size, whereas the metric system is more commonly used in the U.K. and other countries. We will make sure to use both where we can, but will default to inches.
Other important terms to remember when dealing with trim size include the following:
- Font: The font choice and size will affect the page count of your book, which could influence your choice of trim size.
- Line spacing: Like font choice, the space between lines will affect the page count of the book.
- Margins (including Gutter Margins): The empty space that surrounds your text. Your gutter margin will be larger than the rest, so your text doesn’t get lost in the inside crease of your book.
- Bleed: A term that usually refers to images/illustrations that reach all the way to the edges of the page.
- Color: The thickness of the paper will vary depending on your choices of Black & White, Cream, or Color. IngramSpark, for example, offers fewer sizes for color print books.
If you're using a program to adjust your trim sizes, we recommend Atticus, which will automatically format everything for you, so your trim size, margins, bleed, and all those other pesky details will be taken care of for you.
Why Is Trim Size Important?
Think back to the last time you were in a bookstore. What books caught your eye? Were they the large hardcovers with dramatic covers, or were they the mass market paperbacks perfectly lining shelves?
Readers tend to have different tastes. Some love the solid feel of the thick hardcover. Others (myself included) love the uniform feel of smaller-sized paperbacks on the shelf.
But there are far from just these two options. Children’s books, for example, usually require radically different standard book sizes.
What you choose will have an effect on the reader's experience (assuming they are reading a print book). Depending on what you want for your reader, and the genre you write in, you will need to carefully consider what book size you choose.
Industry Standard Trim Sizes
Generally speaking, there are three classes of trim size that you should consider for your book. Each of these has several common sizes in each, so there is some flexibility. These are:
- Mass-market paperback
You may also hear terms like these thrown around, especially among libraries and publishers, to denote the general size of a book:
- Folio: the largest format
- Quarto: smaller but still large
- Octavo: even smaller
While these terms are handy to know, they are not as important when determining the size of your book, especially when using digital print-on-demand services like KDP Print or IngramSpark.
The hardcover is the industry standard, especially in traditional publishing, for new books released in book stores. They are the largest, the most durable, and take up the most real estate in a bookstore.
They are also the most expensive, and most traditionally published authors will make a lot more money from the sale of a hardcover than a paperback.
Until recently, IngramSpark was the best option for authors who wanted to make hardcovers of their book. But Amazon has launched a hardcover service, which is currently in beta at the time of this writing.
For indie authors, paperbacks will make up the majority of the print books you sell.
Paperbacks likewise have more print size options than hardcover (on both KDP and IngramSpark), and they are cheaper to produce, which means they are less expensive for the reader.
Less common for self-published authors, mass-market paperbacks were originally designed to be the cheapest option for readers, using significantly less paper, and usually lower-quality paper as well.
Mass-market paperbacks are not as common ever since the ebook emerged and took their place in the affordability and convenience markets. However, they still exist, and IngramSpark even has some paperback printing options in their size. KDP does not.
Trim Sizes in KDP and IngramSpark
While there are other print-on-demand services, many if not most self-published authors use either KDP Print or IngramSpark. While this is not a review of either, the reasons for one or the other usually come down to the following:
- KDP is convenient and easily syncs up with your KDP ebook. There is also no setup fee required.
- IngramSpark has a larger variety of print options, a greater possibility of getting your books in bookstores, but also has a $50 setup fee for each book.
Let’s take a look at what each service has to offer in print sizes.
|Trim Size||KDP||IngramSpark||Includes Hardcover|
|4 x 6” (154 x 102mm)|
|4 x 7” (178 x 102mm)|
|4.25 x 7” (178 x 108mm)|
|4.37 x 7” (178 x 111mm)|
|4.72 x 7.48” (190 x 120mm)|
|5 x 7” (178 x 127mm)|
|5 x 8” (203 x 127mm)||IngramSpark Only|
|5.06 x 7.81” (198 x 129mm)|
|5.25 x 8” (203 x 133mm)|
|5.5 x 8.25” (210 x 140mm)|
|5.5 x 8.5” (216 x 140mm)||Both|
|5.83 x 8.27” (210 x 148 mm) A5||IngramSpark Only|
|6 x 9” (229 x 152mm)||Both|
|6.14 x 9.21” (234 x 156mm)||Both|
|6.5 x 6.5” (165 x 165 mm)|
|6.625 x 10.25” (260 x 168mm)|
|6.69 x 9.61” (244 x 170 mm)||IngramSpark Only|
|7 x 10” (254 x 178 mm)||Both|
|7.44 x 9.69” (246 x 189mm)|
|7.5 x 9.25” (235 x 191mm)||IngramSpark Only|
|8 x 8” (203 x 203mm)||IngramSpark Only|
|8 x 10” (254 x 203mm)||IngramSpark Only|
|8 x 10.88” (276 x 203mm)||IngramSpark Only|
|8 x 10.88” (276 x 203mm)|
|8.25" x 8.25" (210 x 210mm)|
|8.25 x 10.75” (273 x 210mm)||IngramSpark Only|
|8.25 x 11” (279 x 210mm)||KDP Only|
|8.268 x 11.693” (297 x 210mm)|
|8.5 x 8.5” (216 x 216mm)||IngramSpark Only|
|8.5 x 11” (280 x 216m)||IngramSpark Only|
Note: While KDP Print does now have hardcovers in beta, it does not offer hardcovers with a dust jacket. IngramSpark does.
While IngramSpark clearly has a lot more options, bear in mind that the vast majority of authors will not need most of these sizes. Most fiction or non-fiction authors can probably get by with 5 x 8”, 5.5 x 8.5”, or 6 x 9”.
Which Trim Sizes are the Most Common?
If the table above was too overwhelming, don’t worry. Most of these sizes are not necessary for the vast majority of fiction and non-fiction authors.
To make it a little easier for you, here are some of the most common sizes in traditional and indie publishing.
- Mass market paperbacks: 4.25 x 6.87”
- Trade paperbacks (most common for indie authors): 5 x 8”, 5.5 x 8.5” or 6 x 9”
- Novellas: 5 x 8”
- Fiction hardcovers: 6 x 9”
- Comic books: 6.625 x 10.25”
- Textbooks: Vary from 6 x 9” to 8.5 x 11”
There is some variation depending on the genre, which I’ll cover below, but these are the standard sizes for most of the industry.
What if You Need an Unusual Size?
On the off chance that you need a size that is not covered by KDP or IngramSpark, you can find offset book printing companies to do the work for you.
For example, let’s say that you want a children’s book that is only four inches tall, but eleven inches wide. An offset printing company could do this for you, as they can handle most unusual print sizes.
Another example would be a book with special needs, such as foldable inserts.
However, offset printing companies are significantly more expensive and time-intensive than a regular digital printing company. So expect to pay upfront and extra for the service.
In other words, only use an offset printing company if you absolutely have to. I recommend trying to make it work with KDP or IngramSpark first.
What Trim Size Should I Pick?
There are four factors to consider when choosing a trim size:
- Genre/book type: Epic fantasy, for example, will expect thicker books, while children’s books are better with a wider trim so as to allow for larger images and words.
- Cost: The size will affect how much paper is used to print your book, which can affect cost.
- Marketability: related to the previous two, size is often a determining factor on the placement of your book in a bookstore, or on a reader’s shelf.
- Your personal taste: I mention this only because you should like the size that you choose, within reason.
Let’s cover each of these in more detail.
While there are no hard and fast rules about what trim size you should have for each genre, there are a number of trends and suggested sizes for each.
For example, a huge epic fantasy might benefit from a larger print size, because having a huge doorstopper of a book is expected for that genre.
On the other hand, you might want a smaller print size for a horror or thriller, so there are fewer words on each page, making the reader feel like they are flying through the book.
Here are the more common sizes for various book types:
- For fiction: 4.25 x 6.87” (mass market paperback), 5 x 8”, 5.25 x 8”, 5.5 x 8.5”, or 6 x 9”
- For novellas: almost always 5 x 8”
- For children’s books: 7 x 10”, 5 x 8”, 11 x 8.5”, or 8.5 x 8.5”. Children’s books tend to vary more widely than other types.
- For non-fiction: 5.5 x 8.5”, 6 x 9”, 7 x 10”.
- For memoirs: 5.25 x 8”, 5.5 x 8.5”
Art and photography books are another consideration, but there are no set standards for these. Choose whatever you feel is best. I would personally recommend one of the square sizes for a photography book, but almost anything will do if it fits the aesthetic you are looking for.
In most cases, especially if you are using KDP Print or IngramSpark, the larger your trim size, the more expensive your book will be to produce.
This is true, even if the larger print size results in a lower page count by fitting more words on each page.
What this means is that your book will be more expensive to the reader, which could drive down sales.
Despite this, you don’t necessarily want to pick the cheapest option possible. Sometimes having a large book is necessary, depending on the needs of the market and the readers’ expectations.
Additionally, if you’re trying to increase ebook sales, having a really expensive paperback could make it seem like the ebook is a much better deal. So while cost is something to consider, it’s not the end of the world if your book is more expensive to produce in print form.
Consider your audience. What do they like? Where are they reading?
Are they reading on the go? If so, you might want a smaller print size to be easier to transport.
Are they reading at home in their cozy arm-chair, or perhaps they have poor eyesight? In this case, a larger book with a larger font size might be in order.
Ultimately, I can’t list every instance when you would want a larger or smaller trim size. So our best recommendation is to study the genre.
Go to a bookstore, take a tape measure or ruler with you and look at the books that are sitting on the shelves. You’ll probably find a lot of variation, but also some general trends in your genre.
Pay close attention.
As you can see, there is still a wide degree of options for each category, and there are no set rules.
That is why, ultimately, it comes down to what you want.
While we do recommend staying within the general guidelines outlined above (don’t go publish a novella at a 8.5 x 11” trim size, for example), it’s ultimately up to you.
Personally, I prefer 5 x 8” for my fiction, because I like smaller books, and I try to keep it as consistent as possible because I like how uniform everything looks on my shelf.
But that’s just me. You may have a completely different opinion and that is fine.
Which Will You Choose?
I’ve given you my suggestions, along with a wide variety of options, and a comprehensive look at what KDP Print and IngramSpark have to offer.
Now it’s your turn. What will you choose? Leave your comments down below. I’d love to hear your choices, and your reasoning behind them.