KDP Formatting

What File Format Does KDP Accept? Complete Guide

TL;DR

KDP accepts DOCX, PDF, EPUB, KPF, MOBI (legacy) and HTML for manuscripts; covers must be JPEG, TIFF or PDF. For paperback, export PDF/A (ISO 19005-1) with embedded fonts, 0.125 inch (3 mm) bleed and images at 300 DPI. EPUB is now Amazon's preferred Kindle format. Print proof copies cost £5-£15. Gutter margins should grow for books over 150 pages. Run a KDP Readiness Score on publishing.co.uk to confirm your file is upload-ready.

Last reviewed by Robert Prime — March 2026



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.

Introduction: Why KDP File Formats Matter

If you’re an author self-publishing through Amazon’s Kindle Direct Publishing (KDP) platform in the UK, understanding the right file formats is not just a technical necessity—it’s a commercial imperative. The file format you submit affects everything from how your book appears on Kindle devices and in print to your sales potential.

From my 25 years navigating e-commerce and Amazon marketplaces, I’ve learned that many UK authors underestimate this step. When I wrote Google. Panic. Repeat., the formatting nightmare was on a different level. Despite my technical background, getting the manuscript into a KDP-ready format cost me hours of frustration and wasted money on inadequate freelancers.

Before building publishing.co.co.uk Service | From £25 automated | High-quality, UK-specific formatting | | Print Proof Copy | £5 – £15 per copy | Vital for checking print quality | | ISBN Barcode (if separately purchased) | £15 – £25 | Some providers charge extra for barcode images | | Software Licences (e.g., Adobe InDesign) | £20 – £50 per month | Optional, depends on your workflow |

Many UK authors try to DIY their formatting to save money, but poor formatting can cost sales and credibility. Investing wisely here is crucial.


Comparison with Alternative Publishing Approaches

Self-publishing on KDP is not the only route for UK authors. Here’s how it stacks up against alternatives:

ApproachProsConsUK Market Notes
Amazon KDP (Self-Publishing)Wide distribution, low upfront costs, quick turnaroundTechnical complexity, royalty cuts, limited control over retailDominates UK self-publishing market; high competition
IngramSpark (Print-on-Demand)Better distribution to UK bookstores and libraries, UK printingSetup fees (£49), file formatting strictness, longer approval timesPreferred by authors targeting UK retail channels
Traditional PublishingProfessional editing, marketing, UK retail reachHard to get accepted, low royalties, loss of rightsStill dominant for print and prestige in UK
Hybrid PublishingProfessional support with some rights retainedCostly, quality varies widelyGrowing but less common in the UK
Direct Sales via WebsiteHigher royalties, full controlMarketing burden, logistics for printViable for niche UK audiences but requires effort

For UK authors serious about retail presence beyond Amazon, owning your ISBN and preparing flawless KDP files is essential even if you use IngramSpark or hybrid routes.


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.

Further reading from official sources

About this guide

Written by Robert Prime 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

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Robert Prime

Robert Prime

Robert Prime is a best-selling self-published author, veteran eCommerce strategist, and the founder of publishing.co.uk.

Robert Prime — Founder of publishing.co.uk

About the Author

Robert Prime

Robert Prime is the founder of publishing.co.uk and a co-owner of LoveReading.co.uk. A Forbes Business Council member with 25+ years in eCommerce, he writes about Amazon KDP strategy, scaling indie author businesses, and the commercial side of self-publishing.

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