CMYK vs RGB for Book Covers: Why Your Colours Change in Print

Your cover glows on screen. Then the proof copy arrives, and the electric blue sky has turned a bit grey and the red title looks tired. Nothing went wrong with your printer. You've just met the difference between RGB and CMYK. The short answer: a printed book cover needs CMYK, an ebook cover needs RGB, and the switch from one to the other is where colours change. Here's why it happens, what Amazon KDP and IngramSpark ask for (checked against their own guidance on 3 November 2026), and how to check your file in Canva, Photoshop and Affinity.

Key takeaways#

• Screens make colour from light (RGB). Printers make colour from ink on paper (CMYK). Ink can't reach some of the brightest screen colours, so they print duller.
• For a printed cover, both KDP and IngramSpark ask for CMYK images in the cover PDF. Ebook covers are the opposite: both want RGB.
• If you upload RGB, IngramSpark converts it to CMYK before printing, and says any colour shift is the publisher's job to fix.
• Canva designs in RGB, but its PDF Print download can export CMYK on paid plans.
• Soft-proof on screen, then order a printed proof. It's the only way to see your real colours.

What's the difference between CMYK and RGB?#

They're two ways of describing colour, built for two different jobs.

• RGB stands for red, green and blue. It's how screens work. Your monitor, phone and Kindle mix those three colours of light, and the more light they add, the brighter the colour gets, all the way to white.
• CMYK stands for cyan, magenta, yellow and key (black). It's how printers work. Ink is laid on paper and soaks up light, and the more ink you add, the darker the colour gets.

Because a screen makes its own light, RGB can show colours that ink simply can't reach. Printers call the range of colours a system can make its gamut, and the RGB gamut is bigger. So when a cover moves from screen to paper, some colours have to be squeezed into the smaller CMYK range.

Why do colours change in print?#

Three things usually happen when an RGB cover is printed.

1. 1Bright colours go flat. Neon pinks, vivid greens, electric blues and bright oranges sit outside what CMYK ink can print. They get pulled to the nearest colour ink can make, which is usually duller.
2. 2Dark areas get darker. On screen, a deep navy background still has detail. In ink, it can turn into a solid block, and fine detail in the shadows can disappear.
3. 3The paper changes the picture. A printed cover reflects room light instead of shining it at you, and the lamination changes it again. Gloss keeps colours richer, while matte softens them. Our guide to matte vs glossy book covers explains how each finish affects the look.

There's also normal variation in print-on-demand. KDP's own cover guidance says it works within acceptable levels of colour tolerance and that most variance comes from environmental and mechanical factors, not your file. A good file reduces the risk, but two copies printed on different days won't always be identical.

What KDP asks for#

For paperback and hardcover covers, KDP's cover guidance says images should be in CMYK colour so your cover looks good in print, at a minimum of 300 DPI. It also says:

• Don't include colour profiles. KDP says they can produce unexpected results and are removed automatically before publishing.
• Don't use spot colours, such as Pantone colours. They're made for offset printing, so KDP recommends converting them to CMYK.
• Don't mix colour spaces in one file, for example an RGB photo inside an otherwise CMYK cover, because it can cause colour variance.

Your cover also has to be a single PDF with the back cover, spine and front cover as one image. If you're still working out the full-wrap size, our guide to book cover size on Amazon KDP covers the dimensions and bleed, and how to calculate spine width shows how your page count sets the spine.

Ebook covers are different. KDP asks for an RGB image in JPEG or TIFF format, with ideal dimensions of 2,560 pixels high by 1,600 pixels wide.

What IngramSpark asks for#

IngramSpark's File Creation Guide is stricter and more detailed. For print covers it lists:

• Colour space: CMYK, and all images in a cover file must be CMYK.
• Total ink of no more than 240%. That's the four ink percentages added together. Files over that may be sent back for correction.
• Rich black of 60% cyan, 40% magenta, 40% yellow and 100% black for large black areas.
• 100% black only for text of 24 pt or below, so small type stays crisp.
• A PDF/X-1a:2001 or PDF/X-3:2002 file at 300 ppi.

Its guide also says RGB files will be converted to CMYK before printing, which may produce unexpected colour, and that any dissatisfaction with colour shift is the publisher's responsibility to correct. In other words, if you upload RGB, you're letting the printer make the colour decisions for you.

For ebooks, IngramSpark says front covers must be RGB JPG files.

Is Canva CMYK or RGB?#

Canva designs in RGB. That's why your colours look so bright while you work. When you're ready to print, Canva's PDF Print download lets you pick RGB or CMYK as the colour profile, at 300 dpi, with crop marks and bleed. Canva's help centre says the CMYK option is on its paid plans, including Canva Pro and Canva Teams.

To export a print cover from Canva:

1. 1Select Share, then Download.
2. 2Choose PDF Print as the file type.
3. 3Choose CMYK in the colour profile setting.
4. 4Download, then open the PDF and check it before you upload.

If you're on Canva's free plan, your PDF will be RGB. You can still upload it, but expect the printer to convert it, and order a proof so you can see the result.

How to check and convert in Photoshop and Affinity#

In Photoshop, you can preview print colours before you commit. Go to View, then Proof Setup, and pick a CMYK setting, then switch on Proof Colors. View, then Gamut Warning, greys out the areas that ink can't print. When you're happy, Image, then Mode, then CMYK Color converts the file. Save it as a copy so your RGB master stays untouched.

In Affinity, set the document's colour format to CMYK from the Document menu, then export with one of the PDF/X presets. Check which PDF/X version your printer asks for, since IngramSpark names PDF/X-1a:2001 or PDF/X-3:2002.

Whatever software you use, look at the converted file at full size. If a key colour, such as the title, has dropped badly, adjust it in CMYK rather than hoping it prints brighter.

How to keep your cover colours on track#

• Start in the right place. If you know the cover is for print, pick colours that ink can actually reproduce, rather than neon brights you'll lose later.
• Check your darks. Large dark backgrounds and moody photography need a little more lift than you think, especially on matte.
• Keep small text in pure black. It prints sharper than a four-colour black.
• Order a printed proof. A screen can't show you ink on paper. Hold the proof in daylight and under a lamp before you hit publish.
• Remember the inside too. Colour doesn't stop at the cover. If you'd like a refresher on every part of a printed book, see our labelled guide to the parts of a book.

When you'd like a designer to handle it#

Colour is one of the quiet reasons a home-made cover looks home-made in print. Our designers build every print cover with the printer's colour rules in mind and supply files ready for KDP and IngramSpark. Book cover design packages start from £197 ($249) for an ebook front cover. The Print Ready package is £297 ($377) and includes the full wrap with spine and back cover, ISBN barcode placement, two concepts and three revision rounds. The Launch Bundle is £397 ($497) if you also need an audiobook cover and social graphics.