CMYK to RGB Converter

CMYK is the language of print; RGB and hex are the language of screens. This converter shows a color in all three at once — edit the cyan/magenta/yellow/black percentages, the RGB triple, or the hex code, and everything else recalculates live. It runs entirely in your browser and is handy for translating a brand color from a print spec to a web value.

How to use the CMYK to RGB Converter

Use the color picker for a quick start, or type into any field. Editing the HEX or RGB value recomputes the CMYK percentages; editing any of the four CMYK boxes recomputes the RGB and hex. The preview swatch and the summary line update with every change.

CMYK values are entered as whole-number percentages from 0 to 100 — cyan, magenta, yellow, and key (black) in that order. Because the on-screen color is always RGB, the swatch shows the RGB equivalent of whatever CMYK you enter, which is the closest screen approximation of that ink mix.

Everything is computed locally with the standard device-independent formula. For exact press output you would still soft-proof through your printer's ICC profile, but for design work, mockups, and getting a web color that matches a print spec, this conversion is the practical tool.

Why CMYK and RGB never match perfectly

RGB and CMYK are built on opposite physics. RGB is an additive model: a screen starts black and adds red, green, and blue light, and at full strength those three combine to make white. CMYK is a subtractive model: paper starts white and ink absorbs (subtracts) light, so cyan, magenta, and yellow pigments combine to darken toward — in theory — black. Because one system emits light and the other absorbs it, the two describe color in fundamentally different ways, and translating between them is always an approximation rather than a lossless mapping.

The K in CMYK stands for "key," the key plate that carries the black ink. In principle, equal parts cyan, magenta, and yellow should produce black, but real inks yield a muddy dark brown and use a lot of expensive colored ink to do it. Adding a dedicated black channel produces crisper text, deeper shadows, and cheaper printing. The standard conversion reflects this: it first extracts the black component as K = 1 − max(R, G, B), then expresses the remaining color as cyan, magenta, and yellow relative to what is left after black is removed.

The bigger caveat is gamut. The range of colors a screen can emit and the range a printing press can reproduce only partly overlap. Vivid screen blues and bright greens often fall outside what CMYK inks can achieve, so they shift when printed; some rich CMYK colors likewise sit outside sRGB. A simple arithmetic conversion like the one here ignores the specific inks, paper, and lighting, so professional workflows use ICC color profiles to map between device-specific gamuts and to soft-proof on screen how a file will actually print. Treat the numbers here as an accurate device-independent starting point — perfect for design and web work, and a sensible first draft for print that you then refine against your printer's profile.

Common use cases

• Print spec to web. Turn a CMYK brand color from a style guide into a hex value for a website.
• Web to print draft. Get approximate CMYK percentages for an existing screen color before sending to a designer.
• Checking ink coverage. See the K (black) component and total ink mix for a given color.
• Learning color models. Watch how additive RGB and subtractive CMYK relate as you adjust values.