Last reviewed by The publishing.co.uk Team — May 2026
Find the perfect trim size for your Amazon KDP paperback. Use the genre selector below to see recommended sizes, or browse the complete filterable table of all available KDP trim sizes.
UK note: UK-specific considerations apply — ISBN purchases go through Nielsen (not Bowker), VAT rules differ from the US (print books are zero-rated; ebooks carry 20% VAT), and GDPR applies to any email/customer data. See our UK self-publishing guides for specifics.
We see this come through our formatting queue at publishing.co.uk regularly, so the patterns and fixes here are based on what actually works at upload.
Choose Your Genre
Click a genre to see the recommended trim sizes and UK publishing conventions:
Fiction / Novels
Non-Fiction / Self-Help
Memoir / Biography
Children's Books
Poetry
Textbooks / Workbooks
Photography / Art Books
Romance
Visual Size Comparison
Sizes shown at relative scale. Click a genre above to highlight recommended sizes.
Complete KDP Trim Size Table
Filter and search all available Amazon KDP trim sizes:
| Trim Size (in) | Metric (mm) | Bleed | No-Bleed | Best For | Notes |
|---|
UK Publishing Size Equivalents
For UK authors, here is how traditional British book formats map to KDP trim sizes:
| UK Format | UK Size (mm) | Closest KDP Size | KDP Size (mm) |
|---|---|---|---|
| A-format (mass market) | 110 x 178 | 5" x 8" | 127 x 203 |
| B-format (standard) | 129 x 198 | 5.25" x 8" or 5.5" x 8.5" | 133 x 203 or 140 x 216 |
| C-format (trade) | 135 x 216 | 5.5" x 8.5" | 140 x 216 |
| Demy | 138 x 216 | 5.5" x 8.5" | 140 x 216 |
| Royal | 156 x 234 | 6.14" x 9.21" | 156 x 234 |
| Crown Quarto | 189 x 246 | 7.44" x 9.69" | 189 x 246 |
You might also need
- Margin Calculator
- Spine Width Calculator
- KDP Cover Formatting Guide
- KDP Formatting Checklist
- Word to KDP Guide
Quick verdict
Use this if:
- You're publishing your first 1-3 books and want a fast workflow
- You don't want to learn complex software
- Cross-platform compatibility matters
Skip it if:
- You're publishing 10+ books and need granular control
- Your books have complex layouts (cookbooks, picture books)
- You already have a workflow that works
Best alternative: depends on your priority — speed (paid tool), price (free Calibre), or polish (paid service).
Frequently asked questions
Can I do this in Word or do I need specialist software?
Word can produce KDP-acceptable files but takes effort. Tools like Atticus, Vellum, or Reedsy Editor are faster for novels. For complex layouts (cookbooks, picture books) Adobe InDesign is the professional standard.
What's the minimum quality bar for KDP acceptance?
Embed all fonts, 300 DPI for any images, no bleed unless declared, trim size matched between cover and interior, single-page PDF for cover (not separate front/back). KDP accepts about 90% of files that meet these basics.
How long does the formatting process take?
DIY: 10-30 hours first time. Using a tool with templates: 2-6 hours. Paid service: 24-72 hours and no learning curve.
Should I order a proof copy before going live?
Yes — always. Proof copies are £4-£8 each and catch issues monitors don't show: paper bleed-through, spine alignment, cover gloss/matte feel.
Related Tools
About this guide
Written by The publishing.co.uk Team for publishing.co.uk. Last reviewed May 2026. Specs and pricing change — verify current figures with the linked sources before relying on them.
External references
- Amazon's official spec is at KDP's Help Centre.
