Publishing an ebook
An ebook is your book as an EPUB file — the format every major store except Amazon takes directly, and that Amazon accepts and converts. Unlike a PDF, an EPUB is reflowable: the reader's device chooses the font, the size, and where lines break, so your book adapts to a phone, a tablet, or a 7-inch e-reader. That's the mental shift — an ebook is your content, not your print layout. Trim size, margins, and page breaks don't apply; the cover, the text, the chapters, and the metadata do.
Make your EPUB
One command, from your book folder:
unipress compile . --variant book --format epub --out my-book.epubThis uses your final variant, so it picks up your covers — the front cover becomes the ebook's thumbnail — your chapters, and your title and author. You get my-book.epub, ready to upload.
Validate before you upload
Stores reject EPUBs that don't meet the standard, and a bad file can fail after you think you've published. Check yours first with epubcheck, the official validator:
- Online: the EPUBCheck validator (or search "epubcheck online").
- A green result means every store will accept the file.
unipress produces valid EPUBs, but validating takes a minute and rules out a whole category of upload problems — always do it.
Where to sell it
Two strategies, and many authors use both:
Direct to each store
Open an account with each retailer and upload your EPUB. More work, but you keep the larger share and get each store's full tools and reporting.
| Store | Reaches | Sign up |
|---|---|---|
| Amazon KDP | Kindle — the largest ebook market | kdp.amazon.com |
| Apple Books | Apple devices | authors.apple.com |
| Kobo Writing Life | Kobo, and libraries via OverDrive | kobo.com/writinglife |
| Google Play Books | Android and the web | play.google.com/books/publish |
Through an aggregator
Upload once; the aggregator distributes to many stores and pays you. Less work, and they take a small cut. The main two:
- Draft2Digital — the popular default; reaches Apple, Kobo, Barnes & Noble, and more (you can still do Amazon yourself).
- Smashwords — now part of Draft2Digital; broad reach including library channels.
A common setup: KDP directly (for Amazon's reach and terms) plus an aggregator for everywhere else.
Pricing and royalties
Each store pays a royalty — a percentage of your list price — that depends on the price you set and the store's terms. Amazon, for example, offers a higher royalty band for ebooks priced within a middle range and a lower one outside it; other stores have their own rules. Set your price on each store's dashboard, and read its current royalty terms there — the numbers change, so trust the store over any guide (including this one). As a starting point, look at what comparable books in your category charge.
A few practical notes
- Cover thumbnail. Kindle and most stores want a tall cover of at least ~1600 × 2560 px — the same front-cover image unipress already uses. See Covers and images.
- DRM. At upload each store asks whether to apply DRM (copy protection). Most independent authors publish DRM-free; it's your call and it's reversible only in one direction, so decide deliberately.
- ISBN. An ebook doesn't strictly need one on every store (Amazon issues a free internal ID), but some stores prefer or require an ISBN. See ISBNs and metadata.
- Metadata. Title, description, categories, and keywords are entered on each store, not baked into the file. Getting them right is how readers find you — see ISBNs and metadata.
Next
- Also selling in print? See Publishing in print.
- Sort out your ISBN and metadata.