Wondering what size books KDP prints? Amazon KDP offers 16 paperback sizes and 5 hardcover sizes. Choosing the right KDP book size is more important than you might think—it affects production costs, reader perception, genre fit, and shelf appeal.
What Size Books Does KDP Print?
Amazon KDP prints books in a variety of standard dimensions. The most popular Amazon KDP book sizes are:
- 6×9": The most popular KDP book size for non-fiction and novels
- 5.5×8.5": Great for memoirs and trade paperbacks
- 8.5×11": Standard for workbooks, journals, and coloring books
- 5×8": Compact size popular for mass-market style books
Why Trim Size Matters
Your book's trim size (the final dimensions after cutting) impacts:
- Printing costs: Larger books cost more to print
- Reader expectations: Each genre has standard sizes readers expect
- Shelf presence: Size affects how your book looks in bookstores
- Shipping costs: Larger dimensions = higher shipping fees
- Page count perception: Same content in different sizes creates different page counts
💰 Cost Impact Example
A 200-page book at 6×9" costs approximately $3.65 to print. The same book at 8.5×11" costs $4.50 – that's 23% more expensive. Choose wisely!
All 16 KDP Paperback Trim Sizes
Amazon KDP offers these paperback trim sizes. Here's what you need to know about each:
Standard Sizes
- 5×8": Compact and portable, great for mass-market feel
- 5.5×8.5": Popular for memoirs and smaller books
- 6×9": ⭐ Most popular – perfect for novels, memoirs, non-fiction
- 7×10": Larger format for textbooks and technical books
- 8.5×11": Standard letter size for workbooks and journals
International Sizes
- 5.06×7.81": European B-format (129×198mm)
- 6.14×9.21": European standard (156×234mm)
- 8.27×11.69": A4 size, common in Europe and Asia
Specialty Sizes
- 5.25×8": Slightly wider than 5×8", unique positioning
- 6.69×9.61": European Großformat
- 7.44×9.69": Another European option
- 7.5×9.25": Between standard 6×9 and 8.5×11
- 8×10": Square-ish format for photo books
- 8.25×6": Landscape orientation
- 8.25×8.25": Square format for children's books
- 8.5×8.5": Larger square format
Complete Trim Size Comparison Table
Here is every KDP paperback trim size with details on best use cases, available paper options, spine text eligibility, and popular genres at a glance:
| Trim Size | Best For | Paper Options | Spine Text Min Pages | Popular Genres |
|---|---|---|---|---|
| 5×8" | Mass-market style books | White, Cream, Color | 79 | Romance, Poetry, Devotionals |
| 5.06×7.81" | European B-format | White, Cream, Color | 79 | UK/EU fiction, Literary fiction |
| 5.25×8" | Trade paperback alternative | White, Cream, Color | 79 | Novels, Memoirs, Self-help |
| 5.5×8.5" | Trade paperback standard | White, Cream, Color | 79 | Memoirs, Fiction, Business |
| 6×9" | Most popular – all-purpose | White, Cream, Color | 79 | Non-fiction, Novels, Textbooks |
| 6.14×9.21" | European standard (156×234mm) | White, Cream, Color | 79 | EU non-fiction, Academic |
| 6.69×9.61" | European large format | White, Cream, Color | 79 | EU textbooks, Illustrated |
| 7×10" | Textbooks, technical manuals | White, Cream, Color | 79 | Textbooks, How-to, Reference |
| 7.44×9.69" | European specialty | White, Cream, Color | 79 | EU reference, Illustrated |
| 7.5×9.25" | Mid-large format | White, Cream, Color | 79 | Cookbooks, Guides, Workbooks |
| 8×10" | Photo books, cookbooks | White, Color | 79 | Cookbooks, Photo books, Art |
| 8.25×6" | Landscape orientation | White, Color | 79 | Children's, Photo, Landscape art |
| 8.25×8.25" | Square format | White, Color | 79 | Children's, Coloring, Art |
| 8.5×8.5" | Large square format | White, Color | 79 | Coloring books, Children's, Art |
| 8.5×11" | Letter size – workbooks | White, Color | 79 | Workbooks, Journals, Planners |
Already Know Your Trim Size? Calculate Your Exact Cover Dimensions Free
Enter your trim size and page count — our KDP Cover Size Calculator instantly outputs the precise cover width, height, and spine width you need. No math required.
Which Trim Size Should I Choose? Decision Guide
If you're unsure which KDP trim size to pick, use this quick guide organized by book type:
Novels & Fiction
Recommended: 5.25×8", 5.5×8.5", or 6×9"
The 6×9" size is the most versatile and widely used for fiction. If you want a more compact, mass-market feel (common in romance and thrillers), go with 5.25×8" or 5.5×8.5". These sizes keep page counts reasonable and printing costs low.
Children's Books
Recommended: 8.5×8.5" or 8×10"
Square formats (8.5×8.5") are the most popular for picture books because they showcase full-page illustrations beautifully. For early readers with a mix of text and images, 8×10" works well. For chapter books targeting middle grade and up, consider 5.5×8.5" or 6×9".
Coloring Books
Recommended: 8.5×11"
Letter size gives colorists the most space to work with. The 8.5×8.5" square format is also popular for coloring books and can stand out on Amazon. Avoid smaller sizes—colorists want room for detail.
Workbooks & Activity Books
Recommended: 8.5×11"
The standard letter size is expected by readers for workbooks. It provides adequate writing space and is familiar to students and educators. For younger children's workbooks, 8×10" is also acceptable.
Poetry
Recommended: 5×8" or 5.5×8.5"
Smaller, more intimate sizes work best for poetry collections. The compact format feels personal and is traditional for the genre. Cream paper also adds warmth that complements poetry.
Puzzle Books (Sudoku, Word Search, Crosswords)
Recommended: 8.5×11"
Puzzle books need space for grids and writing. The letter size is the industry standard and readers expect it. Some publishers also use 6×9" for travel-sized puzzle books.
Cookbooks
Recommended: 8×10" or 8.5×11"
Cookbooks need room for recipe layouts and food photography. The 8×10" format is a classic cookbook size, while 8.5×11" provides even more space. Use color paper for best results with food images.
💡 Quick Rule of Thumb
When in doubt, choose 6×9" for text-heavy books (novels, non-fiction, self-help) and 8.5×11" for visual or interactive books (workbooks, coloring books, journals). These two sizes cover the vast majority of successful KDP books.
Choosing by Genre
Different genres have different reader expectations. Using the "wrong" size can make your book look unprofessional:
Fiction
- Literary fiction: 5.5×8.5" or 6×9"
- Thrillers/Mystery: 6×9" (industry standard)
- Romance: 5×8" or 5.5×8.5" (mass-market feel)
- Science Fiction/Fantasy: 6×9"
- Horror: 5.5×8.5" or 6×9"
Non-Fiction
- Business books: 6×9" (professional standard)
- Self-help: 5.5×8.5" or 6×9"
- How-to guides: 7×10" or 8.5×11" (room for diagrams)
- Cookbooks: 8.5×11" (space for photos)
- Technical/Academic: 7×10" or 8.5×11"
- Biography/Memoir: 6×9"
Children's Books
- Picture books: 8.5×8.5" or 8.5×11"
- Early readers: 6×9" or 7×10"
- Middle grade: 5.5×8.5" or 6×9"
- Young adult: 5.5×8.5" or 6×9"
KDP Hardcover Sizes (5 Options)
Amazon KDP offers 5 hardcover trim sizes for premium book publishing:
- 5.5×8.5": Compact hardcover, great for literary fiction
- 6×9": ⭐ Most popular KDP hardcover size—works for most genres
- 6.14×9.21": European standard (156×234mm)
- 7×10": Premium format for non-fiction with images
- 8.25×11": Large format for coffee table books and illustrated works
KDP hardcovers are premium products with case laminate finish. The 6×9" hardcover size works for most books, while 7×10" and 8.25×11" are better for illustrated or coffee table books.
Cost Considerations
Trim size directly affects your printing costs and profit margins:
Printing Cost Formula
Amazon charges: Base cost + (page count × $0.012 for black & white) × size multiplier
- 5×8" to 6×9": Standard multiplier (1.0×)
- 6.14×9.21" to 7×10": Medium multiplier (~1.15×)
- 8.5×11": Highest multiplier (~1.4×)
Example: 200-Page Book
- 5×8": ~$3.50
- 6×9": ~$3.65
- 7×10": ~$4.20
- 8.5×11": ~$4.50
That $1 difference might seem small, but if you sell 1,000 copies, it's $1,000 in extra costs eating into your profits.
How Trim Size Affects Your Profit Margins
Trim size is one of the biggest factors in your KDP printing cost, which directly determines your royalty per sale. Here is how it breaks down in 2026:
KDP Printing Cost Tiers by Size
Amazon classifies trim sizes into cost tiers. Books wider than 6.12" or taller than 9" are classified as "large" and cost more per page to print:
- Standard tier (5×8" through 6×9"): Lowest per-page cost (~$0.012/page for B&W). Best profit margins.
- Large tier (7×10", 8×10", 8.5×11", etc.): Higher per-page cost (~$0.015/page for B&W). Necessary for some book types but reduces margins.
- Color printing: Adds significantly to cost regardless of size. Standard color is ~$0.07/page, premium color is ~$0.04/page on top of the base cost.
Profit Margin Comparison Example
Consider a 200-page black & white book priced at $14.99 with 60% royalty (sold on Amazon.com):
- 6×9": Print cost ~$3.65 → Royalty = $14.99 × 0.60 - $3.65 = $5.34 per sale
- 7×10": Print cost ~$4.20 → Royalty = $14.99 × 0.60 - $4.20 = $4.79 per sale
- 8.5×11": Print cost ~$4.50 → Royalty = $14.99 × 0.60 - $4.50 = $4.49 per sale
Choosing 8.5×11" over 6×9" costs you $0.85 per sale. At 500 copies sold, that is $425 in lost profit. Only choose a larger size when your content genuinely requires it (images, worksheets, or reader expectations for that genre).
💰 Maximize Profit: Size Down When Possible
If your book works at both 6×9" and 8.5×11", almost always choose 6×9". The smaller size has lower printing costs, lower shipping costs for expanded distribution, and matches reader expectations for most text-based genres.
See Exactly What You'll Earn Per Sale
Plug in your trim size, page count, and list price into our free KDP Royalty Calculator to compare profit margins across sizes before you commit.
Page Count Impact
The same content creates different page counts in different sizes. A 50,000-word novel might be:
- 250 pages at 5×8"
- 200 pages at 6×9"
- 150 pages at 8.5×11"
Psychological impact: A 150-page book might seem "too short" for a novel, while 250 pages feels substantial. Consider reader perception when choosing size.
📚 Pro Tip: Check Competitors
Search Amazon for the top 10 books in your category. What trim sizes do they use? Matching industry standards helps your book "fit in" with successful titles.
Professional Appearance
Your trim size should match industry standards for your genre. Using an unusual size can make your book stand out—but not always in a good way.
When to Use Standard Sizes (6×9", 5.5×8.5")
- First-time authors establishing credibility
- Genre fiction following market norms
- Books targeting traditional bookstore placement
- Maximizing profit margins
When to Use Unique Sizes
- Children's books (square formats work great)
- Coffee table books (large formats showcase images)
- Workbooks and journals (8.5×11" provides writing space)
- International markets (using local standard sizes)
Spine Width Considerations
Trim size affects spine width calculation. For books under 79 pages, KDP doesn't allow spine text regardless of trim size. For thicker books:
- Wider trim sizes create wider spines at the same page count
- More spine space means easier-to-read spine text
- Consider spine visibility on bookstore shelves
Learn more: Understanding KDP Spine Width
Making Your Decision
Follow this decision framework:
- Research your genre: What do bestsellers in your category use?
- Consider your content: Images? Diagrams? Lots of white space?
- Calculate costs: How does size affect your profit per sale?
- Think about readers: What size will they expect and prefer?
- Test if possible: Order proof copies in different sizes
Not Sure Which Size to Choose?
KDPEasy supports all 16 KDP trim sizes. Generate covers for different sizes and see which looks best.
Frequently asked questions
6" x 9" is the most commonly used trim size, suitable for most fiction and nonfiction genres.
KDP offers 16 standard paperback sizes ranging from 5" x 8" to 8.5" x 11", plus custom sizes (4"-8.5" width, 6"-11.69" height).
8.5" x 8.5" or 8.5" x 11". Square format (8.5" x 8.5") is now the most popular for coloring books.
KDP offers 5 hardcover sizes: 5.5"x8.5", 6"x9", 6.14"x9.21", 7"x10", and 8.25"x11".
Yes. Larger trim sizes (over 6.12" wide or 9" tall) are classified as "large" and have higher per-page printing costs.
8.5" x 11" is the standard for puzzle books (sudoku, word search, crosswords) because puzzle grids need space to be legible. Some publishers use 6" x 9" for travel-sized puzzle books, but 8.5" x 11" is what buyers expect and search for.
No. Once a KDP paperback is published, you cannot change its trim size. To publish in a different size you must create a new title. Plan your trim size carefully before uploading — this is why ordering a proof copy first is so important.
8.5" x 8.5" is the most popular trim size for KDP children's picture books because the square format displays full-page illustrations beautifully. The 8.5" x 11" size also works well for larger picture books. For chapter books aimed at middle-grade readers, 5.5" x 8.5" or 6" x 9" are appropriate.
Bleed refers to content (images, backgrounds) that extends 0.125" beyond the trim line on all sides so there is no white border after the book is cut. If your interior designs go to the edge of the page, select "bleed" and expand your page size to 8.75" x 11.25" (for 8.5" x 11" trim). Most coloring books use "no bleed" and keep designs inside 0.25" margins.
The full cover width is: (page width × 2) + spine width + (0.125" bleed × 2). Spine width is calculated as: (number of pages × 0.002252") + 0.06" for white paper. KDP also provides a free cover template generator in the publishing dashboard where you input your page count and trim size to download a pre-measured template.
KDP requires a minimum of 79 pages before it allows spine text on a paperback. Books with fewer than 79 pages have a spine too narrow to print legibly. If your book is under 79 pages and you want branded spine text, add extra content or blank pages to reach 80+.
Both work well, but 6" x 9" is the de facto standard for business and self-help books on Amazon. It projects a more authoritative presence and slightly lower page count (making books appear less daunting). Choose 5.5" x 8.5" only if you specifically want a more intimate, memoir-like feel or need to keep page count high for perceived value.
Written by Danielle Okonkwo
Marketing & Growth Lead at KDPEasy
Danielle is a published author with 12+ titles on Amazon KDP and a former book blogger. She writes KDPEasy's guides drawing from hands-on publishing experience and years of testing what actually works in the KDP marketplace.
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