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Kobo Requirements

File formats, metadata, and content requirements for publishing on Kobo through Kobo Writing Life. Updated for 2026.

Overview

Kobo at a glance

Kobo is the second-largest dedicated ebook platform after Kindle. It has a strong presence in Canada, the UK, Europe, Japan, and Australia — making it essential for authors who want to reach readers beyond Amazon.

Authors upload directly through Kobo Writing Life (KWL), which is free to use. Kobo is also accessible via distributors like IngramSpark and Draft2Digital if you prefer aggregated distribution.

Royalty (books $2.99+) 70%
Royalty (below $2.99) 45%
Upload cost Free
Subscription program Kobo Plus (opt-in)
File format EPUB
Exclusivity required No
File Specs

EPUB requirements

Kobo accepts EPUB files only. No PDF, MOBI, or DOCX. Your EPUB must be well-formed and pass validation before Kobo will accept it.

Requirement Specification
File formatEPUB 3 preferred, EPUB 2 accepted
ValidationMust pass EPUB Check
Layout (standard)Reflowable
Layout (visual books)Fixed layout supported
Maximum file size1 GB
FontsEmbedded fonts supported
ImagesJPEG or PNG, RGB color space
CSSSubset of CSS3 supported
JavaScriptNot supported
Table of contentsRequired — NCX (EPUB 2) or nav document (EPUB 3)
EncryptionNone — Kobo applies their own DRM
Fixed layout is supported for picture books, comics, and cookbooks. For standard prose fiction and nonfiction, use reflowable EPUB — it provides the best reading experience across Kobo devices and apps.
Cover Image

Cover requirements

Kobo displays your cover image prominently in the store, on device home screens, and in recommendation carousels. A high-resolution, well-designed cover is critical for discoverability.

Requirement Specification
FormatJPEG or PNG
Minimum dimensions1400 × 1873 pixels
Ideal dimensions2500 × 3500 pixels
File sizeUnder 5 MB
Color spaceRGB (sRGB)
Aspect ratioApproximately 1:1.4 to 1:1.6
Tip: Always upload the highest resolution cover you have. Kobo will downscale for different device screens, but it cannot upscale a low-resolution image. A 2500 × 3500 pixel cover looks sharp on high-DPI e-readers and tablets alike.
Metadata

Metadata requirements

Kobo Writing Life collects metadata during the upload process. Complete, accurate metadata improves your book's discoverability in the Kobo store and ensures it reaches the right readers.

Required

  • Title and subtitle
  • Author name
  • Language
  • Description — plain text, no HTML
  • Categories — up to 3 from Kobo's category tree
  • Publication date
  • Price — set per currency (CAD, USD, GBP, EUR, etc.)
  • Age rating

Recommended

  • ISBN — not required, but recommended
  • Publisher name
  • Series name and number (if applicable)
Important: Kobo descriptions must be plain text. Do not include HTML tags, markdown, or rich formatting in your book description. Kobo will reject or strip HTML markup from descriptions.
Subscription

Kobo Plus program

Kobo Plus is Kobo's subscription reading service — similar to Kindle Unlimited, but with one key difference: it does not require exclusivity. You can enroll titles in Kobo Plus while also selling on Amazon, Apple Books, Barnes & Noble, and everywhere else.

  • Opt-in per title: You choose which books to enroll. No all-or-nothing requirement.
  • Revenue model: Based on pages read, similar to Kindle Unlimited's page-read fund.
  • Non-exclusive: Does not require KDP Select exclusivity. Publish wide and still participate.
  • International reach: Kobo Plus is available in Canada, the Netherlands, Belgium, and expanding to more markets. Strong for reaching international readers.
  • Separate payout: Kobo Plus earnings are tracked and paid separately from standard ebook sales.

For authors publishing wide, Kobo Plus is one of the few subscription programs that does not lock you into a single retailer. It is worth testing with backlist titles to gauge reader interest.

Troubleshooting

Common rejection reasons

Kobo reviews every submission before it goes live. These are the most frequent reasons books are rejected or delayed during review.

  1. EPUB fails validation

    Your file must pass EPUB Check. Malformed HTML, missing required metadata, or structural errors will cause rejection. Run your EPUB through the EPUB Check validator before uploading.

  2. Cover image too small or wrong format

    Covers below 1400 × 1873 pixels will be rejected. Use JPEG or PNG in RGB color space. CMYK and TIFF files are not accepted.

  3. Missing table of contents

    Every EPUB must include a navigational table of contents — NCX for EPUB 2, or a nav document for EPUB 3. A TOC within the book content alone is not sufficient.

  4. Description contains HTML markup

    Kobo requires plain-text descriptions. HTML tags like <b>, <br>, or <p> will cause issues. Strip all markup before submitting.

  5. Price set to $0.00 outside a free promotion

    Kobo does not allow permanently free books without prior approval. If you want to run a free promotion, use Kobo's promotional pricing tools.

  6. Links to competing stores

    Do not include links to Amazon, Apple Books, or other ebook retailers within your EPUB content. Kobo will reject books that direct readers to competitors.

  7. Duplicate listing

    Uploading the same book twice — whether under the same or a different title — will be flagged. If you need to update an existing book, use the "Edit" function rather than creating a new listing.

  8. Content not matching the declared language

    If you set the language to English but the book is in French (or vice versa), Kobo will reject it. The language metadata must match the actual content language.

Further Reading

Related guides

KDP Requirements File specs, cover dimensions, and metadata for Amazon Kindle Direct Publishing. Apple Books Requirements EPUB specs, cover requirements, and submission guidelines for Apple Books. Barnes & Noble Requirements File formats, metadata, and Nook Press specifications for B&N. EPUB vs PDF Guide When to use EPUB, when to use PDF, and what each format is best for. Formatting Checklist 35-step interactive checklist for formatting your book before upload.
Common Questions

FAQ

What file format does Kobo accept?
EPUB. Kobo Writing Life accepts EPUB 2 and EPUB 3 files. The EPUB must pass validation. Kobo does not accept PDF, MOBI, or DOC files.
Do I need an ISBN for Kobo?
No, but it is recommended. Kobo Writing Life allows publishing without an ISBN by assigning a Kobo-specific identifier. However, having your own ISBN looks more professional and makes your book discoverable through more retail channels.
What is the Kobo royalty rate?
70% for ebooks priced $2.99 (CAD/USD) and above. 45% for ebooks below $2.99. Kobo pays monthly via PayPal or direct deposit, with a 60-day delay from the end of the reporting month.
What is Kobo Plus?
Kobo Plus is Kobo's subscription reading service, similar to Kindle Unlimited. Authors opt in per title and earn revenue based on pages read. Unlike Kindle Unlimited, Kobo Plus does not require exclusivity — you can be on KDP and Kobo Plus simultaneously.
Can I publish a print book on Kobo?
Not directly through Kobo Writing Life. Kobo is an ebook-only platform. For print editions, use KDP (Amazon), IngramSpark (bookstores and libraries), or Barnes & Noble Press. IngramSpark can distribute print books to Kobo's partner bookstores.
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