EPUB Cover Changer (.site) / EPUB cover size
EPUB cover size: which one to use
A cover shaped about 1:1.6 (for example 1600×2560 pixels) is a safe store standard. For the sharpest result on a given screen, match its pixel size: 1072×1448 for 6-inch, 1264×1680 for 6.8–7 inch, 480×800 for a small 4.3-inch reader.
Last updated: · What changed: Added a Calibre/Sigil comparison, a file-privacy note beside the tool and a not-affiliated statement; site name now EPUB Cover Changer (.site); added an About page.
Typical sizes by screen
| Screen class | Pixels (w×h) | Shape |
|---|---|---|
| 6-inch e-reader | 1072×1448 | about 3:4 (1:1.35) |
| 6.8–7 inch e-reader | 1264×1680 | about 3:4 (1:1.33) |
| Small 4.3-inch reader | 480×800 | 3:5 (1:1.67) |
| Store standard | 1600×2560 | 5:8 (1:1.6) |
These are typical sizes for common screens. Check your own reader’s specifications if you need an exact match; the “Keep original size” preset leaves your picture’s size alone (up to 4096 pixels on the long side).
Why shape matters more than size
Readers scale a cover to fit the screen, so a larger picture does not look sharper than one at the screen’s pixel size. What matters is the shape. A picture with a different shape from the screen is cropped or padded, which gives the black borders many people see. The tool’s Fill mode crops to the shape you choose and Fit keeps the whole picture and adds padding in white, black, a custom colour or a blurred copy of the edges.
Open the cover changer
Pick your EPUB and a picture. The book is processed on your device and never uploaded.
Open the cover changerJPEG or PNG
JPEG is the better choice for covers. It is much smaller than PNG for photographs and artwork, and every reader can show it. PNG can carry transparency, which some readers draw as a black background, and a PNG cover can be a few megabytes for no visible gain. Some readers also fail on progressive JPEG or WebP covers, so the tool always writes a baseline JPEG at a quality setting of 90%.
File size
A cover at 1600×2560 as a JPEG is usually a few hundred kilobytes up to about a megabyte, depending on the picture. That is small against the book itself. Flat text covers compress even smaller. There is no reason to go beyond the screen’s size.
Grayscale and e-ink
Most e-ink screens show shades of grey, and some show limited colour. A colour cover is still fine; the reader converts it. What works best is strong contrast: dark text on a light background, or the other way round, and no thin pale lines. The “See it in e-ink grey” switch in the tool shows a grey preview so you can check legibility before downloading. The file you download stays in colour.
Questions and answers
What is the best EPUB cover size in pixels?
About 1:1.6 in shape, for example 1600×2560 pixels, is a common store standard. For a particular screen, match its pixel size, for example 1072×1448 for a 6-inch e-reader.
Is a bigger cover better?
No. Readers scale covers down to the screen, so extra pixels only make the file larger.
Should the cover be JPEG or PNG?
JPEG. It is smaller and works everywhere. Avoid transparency, which some readers show as black.
What size is a cover for a small 4.3-inch reader?
Typical small readers have 480×800 pixel screens, so a 480×800 cover fills the screen. That is also the picture used when the reader sleeps, if it shows the cover.
What aspect ratio should an EPUB cover have?
About 1:1.6 (width to height) is the common store shape, and many e-reader screens are closer to 3:4. A cover in between is fine, because the reader scales it and pads or crops the difference.
Can I use one cover size for every e-reader?
Yes. A 1600×2560 JPEG is a safe default, because readers scale a cover to fit. Matching a screen’s own pixel size only matters if you want the exact shape with no padding.
How do I avoid black borders?
Match the cover’s shape to the screen, or use Fill mode to crop the picture to that shape.
Ready to change the cover?
Choose your EPUB and a picture. It takes under a minute and the book never leaves your device.
Open the cover changer