One cover, many formats
A cover is not one image. It is one design that gets cut into five or six different shapes, and a reader may only ever see one of them.
You do not get to approve those crops. Most happen automatically, in software, at the moment your book appears on a screen. The only place to influence them is the composition, and the only time to do it is before you draw — not afterward, when the art is finished and every new shape is a rescue job.
The shapes your design has to survive
The print wrap. One continuous sheet: back cover, spine and front cover side by side, with bleed on the outside edges and none at either spine fold. It is the widest thing you will make, and the only one where all three panels have to work as a single image.
The front panel alone. What a store shows. Same artwork, no spine, no back.
The ebook cover. 1600 × 2560 pixels, a ratio of 1:1.6. A 6 × 9 front is 1:1.5. Those are close, which is why the difference gets missed: cropping a 6 × 9 front to ebook proportions costs about 6% of the width, 3% off each side. That is a small amount of image, unless something you care about is sitting in it.
The audiobook square. The harshest crop of the set, because the frame stops being tall at all. It is a rebuild rather than a resize — Audiobook cover art is a square, and that changes everything covers what that costs.
The store thumbnail. The front panel shown small enough that the cover is no longer a picture, just a shape and two or three values. Every store displays at its own size, and those sizes change, so treat it as "about the height of your thumb" rather than a number to design against.
The social crops. Wide banners, squares, tall stories. Whatever proportion a platform wants this year, it will take out of the middle of your image and it will not ask first.
What that means for the composition
Three rules, and they are all about where you put things.
Keep the title and anything critical well inside the middle of the front panel. The print safe area — about 0.25 in inside the trim — is the floor, not the target. It protects you from the guillotine, not from a 3% crop on each side or a square that removes a third of the height. Give the type more room than print alone would demand.
Do not build a design whose meaning depends on the full height. A long vertical drop from a sky at the top to a figure at the bottom is a beautiful thing at 1:1.5 and an incoherent thing at 1:1. If the idea only exists when both ends are present, the idea does not survive the square.
Do not hang the identity of the book on something at an edge. A hand entering from the left. A moon in the top corner. A lighthouse three percent in from the right. These are the first casualties of any crop, and they are usually the element a reader was supposed to remember.
In the Cover Maker. One design produces up to eleven print wrap files across three bindings and four printers, each cut to that printer's own geometry, plus an ebook cover at 1600 × 2560 — and it checks the cover at thumbnail size while you work. Start a book → · about the Cover Maker
Check the square early
The square is the test that fails, so run it first. Make a square selection over the middle of your front panel — no resizing, no squashing, just a square of the same width — and look at what is left.
A design that reads as a rectangle can be unusable as a square, and you would rather find that out while the composition is still a sketch. If you never plan an audiobook edition, the square is still the fastest way to discover that everything holding your cover together lives in the top and bottom eighths of it.
The pieces that are not crops
Three parts of a cover are genuinely different work rather than a different view of the same artwork.
The spine exists only in print. Its width is set by the page count, the paper and the printer, so it is not a fixed piece of design you can draw once and forget — and below a certain length there is nothing to print on. KDP puts text on a spine only above 79 pages. See How to calculate spine width and Designing a spine people can read on a shelf.
The back cover exists only in print, holds the blurb and the barcode area, and has no equivalent anywhere else. What goes on the back cover has the contents.
Anything needing more resolution. A wrap is far wider than a front panel, so artwork that is comfortably sharp on the front can be thin across the whole sheet. That is a supply problem, not a composition one — Resolution: why a good-looking image prints badly.
The order to work in
Decide which editions exist before you design: print, ebook, audio, and which of those you will promote on social. Then compose for the tightest crop in that set rather than the loosest, and let the generous shapes inherit from the strict one.
This costs nothing at the sketch stage. Reversed — a finished tall cover, squeezed afterward into a square and a banner — it costs a rebuild, and the rebuilt versions rarely look like they came from the same book.
Make yours
Everything here is built into the tools, and they are free to use: name your book, bring your manuscript or your artwork, and work as long as you like. You only pay when you want the files without the preview watermark.
Next: Ebook cover size, and why it is not your print front · More: Composition and negative space · The thumbnail test · Book cover dimensions, start to finish