How to Format a Book for Kobo: Requirements & Checklist (2026)

If you plan to sell your eBook anywhere beyond Amazon, Kobo belongs on your shortlist — not as an afterthought, but as a genuine second storefront. Kobo Writing Life, the company’s self-publishing platform, reaches readers in nearly 190 countries, and in some markets Kobo is not the underdog at all: in Canada, where it was born, it outsells Kindle outright. But formatting for Kobo trips up authors used to Amazon’s forgiving uploader, because Kobo accepts one thing for ebooks and one thing only — a clean, valid EPUB file — plus a correctly sized cover and metadata that follows its rules. This 2026 guide shows you exactly how to format a book for Kobo: the EPUB requirements that matter, the cover specs to build to, and the pricing rules that decide whether you earn 70% or 45% in royalties. If you are still fuzzy on how EPUB differs from the other formats floating around, our breakdown of EPUB vs MOBI vs PDF sorts them out first.

By the end you will know which file formats Kobo accepts, the EPUB rules that get enforced, the exact cover dimensions, how to write metadata that sails through review, the two pricing conditions guarding your 70% royalty, and how to validate your EPUB the way Kobo’s own tools do. Finish with the pre-upload checklist and your book is Kobo-ready.

Why Publish on Kobo at All?

Ask a room of indie authors where their non-Amazon sales come from and Kobo’s name comes up again and again — usually right after someone mentions Canada. Kobo was founded in Toronto and remains the dominant ebook retailer there; plenty of authors report Kobo outselling Kindle on their Canadian sales by a wide margin. Beyond Canada, Kobo Writing Life distributes to nearly 190 countries, with real strength in the UK, Australia, New Zealand, Japan, and the Netherlands.

Two structural differences make Kobo worth your effort. First, Kobo never demands exclusivity — unlike Amazon’s KDP Select, which locks your ebook to Kindle for 90-day stretches. Second, Kobo calculates royalties separately for each territory, so aggressive pricing in one country does not drag down your rate in another.

Then there is Kobo Plus, Kobo’s all-you-can-read subscription service: the rough equivalent of Kindle Unlimited without exclusivity handcuffs. Opt titles in and earn from subscription reads on top of regular sales. If you publish wide rather than betting everything on one store, Kobo is the backbone of the non-Amazon half of your business.

What Kobo Writing Life Accepts: File Formats

Here is the single most important technical fact in this guide: Kobo Writing Life accepts EPUB files for ebooks — EPUB 2 and EPUB 3 both work for most novels and nonfiction. What Kobo does not accept is a Word document: Amazon’s uploader will cheerfully convert your .docx, but Kobo expects you to arrive with a finished EPUB in hand.

If you write in Scrivener, Vellum, Atticus, or a similar tool, export directly to EPUB and you are most of the way there. If your manuscript lives in Word or Google Docs, convert it with Calibre or run it through an aggregator — our guide to formatting for Draft2Digital covers a workflow whose EPUB output works beautifully on Kobo too.

Behind the scenes, Kobo converts every uploaded EPUB into its own proprietary Kobo ePub format (sometimes written “kepub”) for Kobo eReaders and apps. The conversion adds enhancements like faster page turns, but it also reinterprets your file — which is exactly why simple, clean formatting survives the trip and exotic styling does not. For a normal reflowable ebook, EPUB is the only serious choice. Fixed-layout EPUBs for children’s picture books and heavily illustrated titles are supported as a separate path, with their own testing procedure later in this guide.

EPUB Requirements: The Rules That Matter

A valid EPUB is not a suggestion on Kobo — it is the entrance exam. Your file must pass EPUBCheck with zero errors before upload. Kobo even publishes its own EPUB-cleaning utility, eCanCrusher, which tells you how often malformed files land in their queue. Warnings deserve attention too: a file that validates with warnings will usually upload, but warnings have a habit of becoming rendering bugs on real devices.

Beyond raw validity, four formatting rules decide whether your book looks professional on Kobo hardware. First, use clean semantic HTML: real heading tags for chapter titles, real paragraphs for body text, real lists for lists. Kobo builds its navigation and accessibility features from your document structure, and fake formatting — bolded paragraphs pretending to be headings — breaks the table of contents.

Second, keep your CSS simple and relative. Size fonts in ems or percentages rather than fixed pixels, avoid absolute positioning, and skip negative margins or indent tricks that fight the reader’s own settings. Kobo owners customize fonts and margins aggressively; your stylesheet should cooperate, not override. (Apple Books is stricter still — EPUB 3 only — as we detail in our Apple Books formatting guide.)

Third, handle fonts deliberately. Embed custom fonts only if the license permits it — most commercial fonts do not, and a stripped font at upload time is a classic source of mangled text. When in doubt, skip embedded fonts and let each Kobo device use its excellent built-in reading fonts.

Fourth, mind images and navigation. Size images sensibly (no multi-megabyte photographs), give every image alt text, and include a working, navigable table of contents — EPUB 3’s nav document or EPUB 2’s NCX file — because Kobo surfaces it in the reader chrome. A book with a broken or missing TOC looks unfinished the moment a reader opens it.

Cover Image Specs for Kobo

Upload your cover separately in the Kobo Writing Life dashboard AND embed it inside your EPUB — the embedded cover is what readers see on-device, the uploaded one drives the store listing. Build the master at 1600 x 2400 pixels (2:3 ratio) in JPG or PNG, working in sRGB color. That size keeps text crisp on high-density screens; much smaller designs trigger low-resolution warnings.

One practical wrinkle: Amazon wants a taller 1.6:1 ratio (1600 x 2560), while Kobo, Apple, and Nook all prefer roughly 2:3. The professional solution is a single master design with extra canvas at top and bottom, from which you export two crops — one at 1.6:1 for Kindle, one at 2:3 for everywhere else. Your branding stays identical while each store gets its preferred geometry.

Design for the thumbnail, because that is where the buying decision starts. Test your cover at 120 pixels wide: if the title is unreadable, simplify. Never upscale a small image to 1600 x 2400 — Kobo’s checks can spot the blur, and so can readers. And use only cover art you own or have licensed: Kobo refuses covers pulled from other books or used without permission, and “I found it on Google” is not a license.

Metadata That Gets Approved

Kobo reviews the words around your book as carefully as the file itself, and sloppy metadata is a top reason titles get bounced. Your title, subtitle, series name, and author fields must contain exactly that and nothing else — no keyword stuffing, no “A Thrilling Bestseller” in the title field, no extra descriptors in the author name. Kobo’s rejection guidance calls extraneous words in these fields unacceptable.

Keep your book description simple — short paragraphs, minimal styling. Front-load the hook, name the audience, and close with credibility such as series information or comparable titles.

Two metadata decisions deserve special care. First, categories: choose accurate ones, and if your book’s main content is erotica, categorize it as Erotica — miscategorized adult content is a standalone rejection reason. Second, the ISBN question: Kobo does not require an ISBN for ebooks and assigns its own identifier if you skip it. Supplying your own is optional but common for wide distribution — our ISBN guide for self-published books explains the one-number-per-format rule.

Public-domain works face extra scrutiny and earn a reduced 20% royalty — plan pricing accordingly if you republish classics.

Pricing & Royalty Rules

Here is where formatting meets money: Kobo pays 70% royalties on ebooks, but only when two conditions are both true. First, your price must sit at or above the regional minimum: $2.99 USD in the United States, $2.99 CAD in Canada, $2.99 AUD in Australia, £1.99 in the UK, €1.99 in the European Union, $2.99 NZD in New Zealand, $15.99 HKD in Hong Kong, and ¥299 in Japan, among others. Second, your ebook price must be at least 20% below the suggested retail price of every physical edition of the same book, if a print edition exists. Miss either condition and your royalty drops to 45%.

A third, quieter rule: the price you give Kobo must be equal to or lower than the lowest price you offer any other retailer. Undercut Kobo elsewhere and they may simply match the lower price when calculating your payment.

The system is flexible otherwise. Kobo evaluates each territory independently: discount to $0.99 in New Zealand and still earn 70% on full-price Australian sales. Payments arrive by electronic funds transfer, usually about 45 days after each month-end, and you need to clear a $50 USD threshold before a payout is issued — early sales may simply roll into the next cycle.

Validate and Test Before You Upload

Never upload an EPUB you have not validated, and never trust a validator alone without eyeballing the result. Start with EPUBCheck — free, definitive, and the same standard Kobo’s own tooling is built around — and fix every error it reports. Kobo also offers eCanCrusher, a free utility that re-zips and cleans EPUB files.

Then test the way readers will actually read: sideload the file onto a real Kobo device or app. For a reflowable EPUB, connect your Kobo eReader by USB, drag the file over, and rename the extension to .kepub.epub — the device then renders it exactly like the store version. (Fixed-layout books use .fxl.kepub.epub.) Browse the whole book: does the TOC navigate, do chapters start cleanly, do images sit right, do drop caps survive?

Pay special attention to anything your CSS tried to be clever about — Kobo’s kepub conversion plus the reader’s own font and margin settings will expose every fragile rule. If something renders oddly, simplify the markup rather than adding more CSS. One validation-and-sideload pass catches the overwhelming majority of problems before Kobo’s review team ever sees your file.

The Final Kobo Pre-Upload Checklist

Run this list top to bottom before every Kobo upload — ten minutes that saves days of back-and-forth with the review team.

• EPUB validates with zero errors in EPUBCheck — fix warnings too; they become rendering bugs on devices.
• Cover built at 1600 x 2400 px (2:3, JPG or PNG, sRGB), embedded in the EPUB and ready to upload separately.
• Navigable table of contents works — every chapter reachable from the reader’s TOC menu.
• Title, subtitle, series, and author fields match the cover exactly — no keyword stuffing or extra descriptors.
• Price at or above the regional 70% minimum ($2.99 USD) and at least 20% below the print edition’s price.
• Categories accurate — Erotica correctly categorized if applicable; public-domain status declared.
• File sideloaded and spot-checked on a Kobo device or app (.kepub.epub), including the cover thumbnail.
• Fonts embedded only with a valid license — or skipped in favor of Kobo’s built-in reading fonts.

Conclusion: Treat Kobo Like a First-Class Storefront

Formatting a book for Kobo comes down to three disciplines: a clean, valid EPUB built with simple semantic markup; a 1600 x 2400 px cover designed to survive the thumbnail; and metadata plus pricing that respect Kobo’s rules — especially the two conditions guarding your 70% royalty. Validate with EPUBCheck, sideload once on a real device, and your book will clear review and look professional on every Kobo eReader and app. In markets like Canada, treating Kobo as a first-class storefront pays for itself many times over.