DocomintCMYK ↔ RGB Converter
Convert between CMYK (print) and RGB/HEX (screen) color values in either direction.
Screens mix light additively (RGB) and printers mix ink subtractively (CMYK) — the two models aren't a simple 1:1 formula swap, which is why a color that looks right on screen can print dull or shifted. This uses the standard textbook RGB↔CMYK conversion formulas so you can sanity-check how an on-screen color will translate before sending a file to print, or bring a Pantone/CMYK print spec back into RGB for a matching web version.
Example: A logo's screen blue at RGB(37, 99, 235) converts to roughly C84 M58 Y0 K8 — worth checking against a printer's proof, since CMYK's smaller gamut can't reproduce every RGB color exactly.
How it works
- Pick a direction — RGB/hex to CMYK, or CMYK to RGB
- Enter the color or the four CMYK percentages
- The conversion runs instantly on your device
Frequently asked questions
Why don't RGB and CMYK colors match exactly?
RGB (screens) mixes light additively and can reach a wider, more saturated range of colors than CMYK (ink), which mixes subtractively on paper. Some RGB colors — especially bright, saturated ones — simply have no exact CMYK equivalent, which is why print proofs sometimes look duller than the on-screen design.
Should I use CMYK values for a website?
No — browsers render in RGB (via hex or rgb()), not CMYK. Use CMYK only when preparing a file for offset or digital printing, and convert back to RGB/hex for anything shown on screen.
Is my color values uploaded anywhere?
No — CMYK ↔ RGB Converter runs entirely in your browser using JavaScript/WebAssembly. Your color values is never sent to a server.