Ebook cover vs. print cover — what gets trimmed?
The Cover Maker produces two different cover deliverables, and they aren't the same shape:
- Print cover — the full wraparound (back + spine + front) at your book's trim size, for KDP/IngramSpark paperback or hardcover upload.
- Ebook cover — your front cover only, at the size ebook stores require: 1600 × 2560 pixels, a 1:1.6 portrait ratio (Amazon Kindle's recommended spec).
The cover is the heaviest thing in your ebook
Worth knowing before you hand the Interior Formatter a cover: on a typical novel the cover image is most of the EPUB. Everything else — 84,000 words of text, the navigation, the styling — is smaller than one photograph.
That matters because Amazon charges a per-megabyte delivery fee on every copy sold at the 70% royalty rate. An oversized cover isn't untidiness; it's a small deduction from every sale you ever make.
So when you add a cover in the formatter, it's fitted to the 1600 × 2560 store size and compressed to a size budget — roughly 250 KB at that spec. A designer's 4000-pixel master typically drops by about 80%, and a cover already at store size by about half, with no visible difference. The retailer downsamples anyway, so there is nothing above the spec to gain.
The budget is in kilobytes rather than a quality setting on purpose: browsers disagree about what a given quality number means, and the same cover can come out twice the size in one browser as in another. Aiming at the size gets the same result wherever you work. There's a quality floor it won't go below — a slightly heavy cover beats a visibly bad one.
Two things it will not do: it never enlarges a cover that's below the spec (that would invent detail and charge you to deliver it), and it never hands back a file bigger than the one you gave it. The formatter tells you what it did, in kilobytes, next to the file name.
Why a sliver gets trimmed
Most print trim sizes are slightly wider than the 1:1.6 ebook shape. To fit your front cover into that taller, narrower frame, the tool crops a thin strip off the left and right edges, centered — nothing is squashed or stretched, and nothing is added.
How much comes off depends on your trim size:
- 6 × 9 in — about 3/16″ (0.19″) off each side.
- 5.5 × 8.5 in — about 3/32″ (0.09″) off each side.
- 5 × 8 in — nothing is cropped (5 × 8 is already 1:1.6).
The top and bottom are kept in full.
What this means for your design
Keep anything important — your title, author name, and key artwork — a little away from the extreme left and right edges, roughly 1/4 inch in. Do that and the ebook crop will never touch it. Full-bleed background art is fine; only the outer sliver of the sides is affected.
If your title runs very wide across the cover, check the exported ebook cover to be sure the first and last letters still have breathing room.
How to export it
Open Export → "Export ebook cover (1600×2560)." You'll get a JPEG at the correct store spec, built from the same art and text as your print cover — so you only design once. Free exports carry the preview watermark; the one-time cover unlock removes it.
Your EPUB file (from the Interior Formatter) automatically embeds this same properly-sized cover, so you don't have to add it yourself.