---
title: CMYK vs RGB: why on-screen colors don't match the print
lang: en
source: https://mindsprt.dev/en/knowledge/cmyk-vs-rgb/
---

# CMYK vs RGB: why on-screen colors don't match the print

*Printing Know-how · 4 min read · 2026-05-20*

> A plain-language explanation of the difference between print's CMYK and screen's RGB color modes, why design files should be in CMYK, and how to avoid color shifts in print.

**Quick answer:** RGB is the 'light' your screen emits; CMYK is the 'ink' used in printing. The two work in opposite ways and CMYK has a smaller gamut, so highly saturated colors print darker and duller. Always build print files in CMYK and soft-proof to avoid color shifts.

## RGB is light, CMYK is ink

Screens use RGB (red, green, blue) light that adds up — the more you stack, the brighter it gets, with white as the brightest. Printing uses CMYK (cyan, magenta, yellow, black) inks that overprint — the more you layer, the darker it gets, and the white comes from the paper itself. Because their color-forming principles are reversed, the same file looks different on screen versus on paper.

RGB can reproduce a wider range of colors (a larger gamut) than CMYK — especially highly saturated neon greens, bright blues and hot pinks that printing inks simply can't reproduce. When converted to CMYK these get darkened and muddied, which is the common complaint that 'it didn't print as vivid'.

## Build design files in CMYK

If you supply files in RGB, prepress has to convert them to CMYK, and the colors shift the moment that conversion happens. The safest approach is to set the document color mode to CMYK from the start, and preview with a print standard (such as Japan Color or ISO Coated) via soft proofing — so you don't discover the color difference only after it's printed.

For large solid blacks, use a 'rich black' (for example C40 M30 Y30 K100) rather than a single K100 for a deeper, fuller result; but keep small text and fine lines as single black to avoid registration ghosting from misaligned overprint.

## FAQ

### Why does the print look darker than my screen?

Because screens emit RGB light while printing absorbs it with CMYK ink. CMYK has a smaller gamut, so highly saturated colors can't be reproduced and get darkened. Convert to CMYK and soft-proof before printing to reduce the gap.

### Should design files be RGB or CMYK?

Build print files in CMYK. If you supply RGB, colors shift during prepress conversion, so it's best to set CMYK from the very start.


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