Book size might be the last thing you should think about when publishing or writing a book, right? Are you surprised how can I read your mind? Well, because it’s a mistake, and I made this too. With a heavy heart, let me tell you that the wrong size can impact a book’s printing cost, professionalism, readability, and even sales.

Sigh.

But if you are here reading about the dimensions of a book, then it means you have thought about it at the perfect time – before it’s too late, right? So don’t worry! I am going to break down everything you need to know about choosing the perfect size for a book that matches your story.

In the end, I have some tips that I learned when I collaborated with professional book printing services. These are going to help you to make the right decision!

Key Takeaways

1. Book size = book dimensions = trim size: These phrases are used interchangeably. So don’t get confused.
2. Learn the difference between paperback and hardcover books, along with different standard sizes. Choose based on your goals and budget.
3. The size you choose affects printing cost, number of pages, readability, and even sales.
4. Each genre has a different book size. I have discussed all genres so you can make an informed decision.
5. Not just genre, there are other factors, such as word count, printing cost, POD, and readability, that one must consider when choosing a book size.
6. Print-on-demand services (like Amazon KDP) only support certain book sizes, so always check what’s available.
7. The trim size impacts your cover design, layout, and how the book looks on shelves.
8. Towards the end, explore common printing mistakes, according to experts, that you must avoid.

What Are Book Sizes / Dimensions / Trim Sizes, and Why Do They Matter?

There is a reason why I added a slash between the words in the heading.

Yes – you got that right.

All three words mentioned are the same.

Book dimensions, or trim sizes, are the width and height of your printed book.

For instance, a popular size is 6″ x 9″, meaning the book is 6 inches wide and 9 inches tall.

Now that you have understood what these are let’s take a look at why they matter so much. As mentioned above, book size impacts many things. This includes:

1. Printing cost: It is simple! Larger books cost more to print.
2. Page count: Smaller trim sizes mean more pages, which can impact costs and spine width.
3. Readability: The book dimension also influences format, which affects font size, spacing, and comfort for readers.
4. Genre expectations: Each genre typically has a set of “standard” trim sizes that readers are used to.
5. Distribution: Some trim sizes are more widely accepted by retailers like Amazon.

So, if you want to show your book in a professional way and keep costs low while making it appealing to readers, choosing the right size is important.

Paperback vs. Hardcover

When it comes to book size, one’s mind immediately goes to the following:

Are trim sizes different in paperback and hardcover books?

Great question!

To answer this question, both formats serve different purposes and have different industry standards.

Paperback Books

Paperbacks are also called “softcovers.” They have flexible and laminated covers. They are lighter in weight and are more affordable.

Common Trim Sizes for Paperback

• 5” x 8” – Common for fiction and novels
• 5.5” x 8.5” – Balanced option for memoirs and self-help
• 6” x 9” – Most popular for nonfiction, business, and academic work

Hardcover Books

Hardcovers are those special “casebound” books. They have rigid covers, and they often come in those special dust jackets (which, by the way, look absolutely gorgeous on bookshelves. I can attest because, as a die-hard Harry Potter fan – the hardcovers look magical on my shelf.)

They are typically used for:

• Children’s books
• Coffee table books
• Special editions
• High-end nonfiction or literary fiction

Common Trim Sizes for Hardcover

• 6” x 9” – Standard for most hardcover books
• 7” x 10” – Used for textbooks or art books
• 8.5” x 11” – Suitable for workbooks or photo-heavy content

Common Standard Book Sizes by Genre

If choosing a trim size is something new for you and you can’t get the hang of it – don’t worry! I have broken down the most popular and common book sizes by genre.

Fiction

Fiction books usually come in a size that makes them easy to read and sell well. No matter if it’s a romance, thriller, or literary story, most fiction is designed to fit nicely in a smaller format. One more thing that you should keep in mind is that when someone is reading fiction, they immerse themselves in engaging stories. This means the size of your book should be easy to hold, keep, and even fold.

Popular Sizes:

5″ x 8″, 5.25″ x 8″, 5.5″ x 8.5″, 6″ x 9″

Why it works:

These sizes are economical (fictional novels are long) for printing and easy to distribute through both online platforms and physical bookstores. They’re also reader-friendly.

Real Examples:

• The Midnight Library by Matt Haig – 5.06″ x 7.75″ (Penguin Books)
• The Silent Patient by Alex Michaelides – 6″ x 9″ (Celadon Books)
• It Ends With Us by Colleen Hoover – 5.25″ x 8″ (Atria Books)

These books are all bestsellers with trim sizes that offer a seamless reading experience while keeping page count and printing costs manageable.

Non-Fiction

When it comes to non-fiction books – they are either self-help, business-related, or educational like textbooks. This means they have text along with infographics. So, for this genre, the book size needs to be such that it supports the support sidebars, callouts, and infographics. But without feeling cramped.

Popular Sizes:

6″ x 9″, 7″ x 10″

Why it works:

These sizes organize information in a clear and professional way. The extra width gives more space for visuals without making the text feel crowded.

Real Examples:

Atomic Habits by James Clear – 6″ x 9″ (Avery Publishing)

Memoirs & Biographies

Now, next on the list, we have memoirs and biographies. These books are highly personal, but when it comes to formatting – experts follow the fiction or non-fiction guidelines depending on the tone. These stories often include emotional pacing, flashbacks, and reflection. The experts suggest choosing a trim size to help guide the reader’s flow.

Popular Sizes:

5.5″ x 8.5″, 6″ x 9″

Why it works:

These sizes keep the text neat and easy to read. A slightly bigger size helps the story flow well without being too much for the reader.

Real Examples:

• Becoming by Michelle Obama – 6.25″ x 9.25″ (Crown Publishing)
• Born a Crime by Trevor Noah – 6″ x 9″ (Spiegel & Grau)

Children’s Books

One thing that you must understand when writing and publishing these books is that children’s book sizes vary by age group. The size typically depends on what you are putting in the book.

Popular Sizes:

• Picture books: 8″ x 8″, 8.5″ x 8.5″, 8.5″ x 11″
• Early readers: 6″ x 9″
• Chapter books: 5.25″ x 8″, 5.5″ x 8.5″

Why it works:

Larger, square shapes are great for full pictures. This style grabs kids’ attention and allows for fun page designs.

Real Examples:

• The Very Hungry Caterpillar by Eric Carle – 7″ x 5″ (landscape)
• Dragons Love Tacos by Adam Rubin – 10″ x 10″ (Dial Books)
• Dog Man series by Dav Pilkey – 5.5″ x 8.25″ (Graphix)

Workbooks & Educational Books

Such kind of books wants functionality. Educational books provide space for children to write, draw, and make notes. So, when choosing a book size for this genre – you need to make sure that you pick the one that offers clear visual separation and does not make the book appear too cramped.

Popular Sizes:

8.5″ x 11″, 7″ x 10″

Why it works:

Bigger sizes are like regular US printer paper, which makes them great for fill-in-the-blank activities and exercises.

Poetry

Poetry books gained popularity because of social media. People and writers use platforms like Instagram to share their poetry. When they got immense love, writers chose to publish their poetry compilation in book form. It was Rupi Kaur’s 2015 debut collection that started the poetry books movement.

Now, these books want space. They have fewer words, minimal illustration, rhythm, and even emotions. So, you need to choose a book size that supports the line length and mood.

Popular Sizes:

5″ x 8″, 5.25″ x 8″, 6″ x 9″

Why it works:

Smaller formats make things personal and help poets manage the rhythm of their work. If your poems have specific spacing or line breaks, this size makes them look purposeful.

Real Examples:

• Milk and Honey by Rupi Kaur – 5″ x 8″ (Andrews McMeel)
• The Sun and Her Flowers by Rupi Kaur – 5.13″ x 7.75″

Choosing Book Dimensions: Other Factors to Consider

If you think that genre is the only factor based on which book sizes are chosen, you are wrong. Here are some other key factors that you must consider when finding the ideal book size:

Word Count and Page Length

A book’s size can significantly affect how it looks and feels. If a book has a high word count but a small book page size, like 5″ x 8″, it can end up being unusually thick. On the other hand, a short book with big pages might seem too thin.

So, it means that you must decide on book size based on word count as well.

For example, a book with 100,000 words could be over 500 pages if it’s small (5″ x 8″), but only 350-400 pages if it’s larger (6″ x 9″).

A tip: Here is a thing that you must understand. Always have fewer pages!

Why?

Because it means that you will have lower printing costs, lighter shipping, and easy handling.

Print-on-demand (POD) vs. Offset Printing

if you’re self-publishing using print-on-demand services like IngramSpark or Amazon KDP, you might have a limited choice of book sizes.

Tip: Before you finish designing your book’s interior, ask your printer or POD provider for a list of the available sizes.

Distribution Goals

You must think about whether you want your book in stores. In libraries? Or just online?

Distributors and bookstores usually like to keep standard book sizes. If your book is unusual or large, it might be harder to find space for it, and it could cost more to store.

Print Cost and The Profit You Are Making

Are you self-publishing? Wow! Congratulations. It’s exciting, I am sure.

But when writing and publishing, I understand you must be doing it for your passion, but don’t you want to earn profit from it?

The size of the book basically affects printing expenses. So, if you are choosing Print on Demand on Amazon KDP or IngramSpark, remember these platforms calculate costs through:

• Page count
• Trim size
• Paper type (white or cream)
• Interior type (black & white or full color)

Smaller book sizes can mean more pages and higher costs. On the other hand, bigger books might end up being more expensive. So, it’s important to find a balance between cost, how the book looks, and what readers expect.

Readability

You are writing a book for readers. If they fail to enjoy it – then what’s the point? Right? Remember that your trim size should match your interior layout. This means that your font size, margins, and line spacing should go well with the size you choose. Otherwise, the book will become difficult to read and may be aesthetically unbalanced.

And we are living in times of Instagram. Where everyone posts stories on what they are reading, so I am sorry – if your is aesthetically unbalanced – no one will even look at it.

Premium Book Printing Service: Mistakes to Avoid

Now that we have covered all the basics about book size, as I promised – here are some common mistakes suggested by experts that you must avoid when taking your book for Premium book printing service.

Remember that deciding on trim size and printing are essential aspects that can make or break your book.

Not Using a Print-Ready Template

Every trim size has unique requirements for margins, bleeds, and layout. So if you used the wrong template or, worse, used no template at all, it can make your text appear off-center or cut it off completely.

Overlooking Bleed Requirements

If your book has, let’s say, images, infographics, or background colors that extend to the edge of the page, you’ll need to account for “bleed.” This extra space makes sure nothing is lost when trimming.

Ignoring File Format Guidelines

Professional book printing companies suggest using only high-resolution PDF files with embedded fonts when printing your book. Submitting a Word document or low-res file can delay printing or result in poor-quality output.

Choosing the Wrong Paper Type

Yes – paper type is also important!

Ever thought about it? No? Right, because same!

Consider your choices for paper weight, color (white or cream), and finish (matte or glossy). These decisions affect your book size as well as how your book looks and feels, and they can change depending on the genre.

Not Ordering a Proof Copy

Lastly, the mistake that we commit may be because of excitement.

We failed to order a proof copy and instead placed a bulk order.

If the book size is not right or there are other problems, these might appear in the bulk of your order. Which means all those books will go to waste. So, it is wise to always order a physical proof before placing a huge order. This will help you make sure that everything that looked perfect on screen looks good in print as well.

Final Thoughts

The book size is important because it affects how readers see it, its price, how it’s printed, and how enjoyable it is. If you’re a first-time author, you should choose a size that:

• Matches your genre
• Fits your budget
• Makes it easy to read
• Looks professional

Take some time to research and compare different sizes. This important choice can help you succeed in the competitive world of publishing. If you are still confused, I would suggest you go out and visit a local bookstore. Look at what publishing companies or your fellow authors are doing with their book size. This will also give you an idea about what’s working best or what’s currently popular in the market.

FAQ’s  

Can I change the trim size of my book after publishing?

Usually, no. If you change the size of your book, you’ll need to reformat your manuscript, make a new cover, and publish it again as a different version. It’s like making a whole new book.

Can book size influence pricing strategy?

Yes. Thicker books are pricey. But remember that printing them also means a high cost. So be wise and select the size that matches both your printing cost and readers’ expectations.

Can I have different trim sizes for different formats (paperback vs. hardcover)?

Absolutely. It’s common for hardcovers to be slightly larger than their paperback counterparts, and each can have a separate ISBN.

How does book size affect bookshelf placement in stores or libraries?

Standard sizes are more likely to fit into bookstore and library shelves easily. Custom or oversized books may face space limitations or be displayed in non-standard ways.

Do eBooks have a fixed trim size like print books?

No, eBooks do not have fixed dimensions. They are designed to be responsive, meaning the content adjusts to the screen size and reader settings (font size, spacing, etc.) on devices like Kindles, tablets, and smartphones.

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About Author

Hi My name is Micheal Adams, When I am not watching horror movies and helping my kids with homework or reading my favorite fantasy/supernatural novels – I’m writing to guide aspiring authors. I focus on exploring and simplifying both the technical aspects and the often-overlooked details of book writing and publishing so I can empower new writers to climb the Amazon bestseller list and connect with more readers.