RGB ↔ CMYK Converter

Turn RGB values into CMYK percentages and back again while copying the exact values with one click.

RGB to CMYK

Enter red, green and blue channel values (0–255) to calculate the matching CMYK percentages.

Each channel must be a whole number between 0 and 255.

CMYK to RGB

Enter cyan, magenta, yellow and key (black) percentages to see the RGB equivalent.

Use values between 0 and 100. Decimals are allowed for finer control.

RGB vs. CMYK

RGB mixes red, green and blue light, which makes it ideal for displays, LEDs and any digital-first workflow.

CMYK blends cyan, magenta, yellow and black inks, which is the standard model for professional printing and packaging.

When to convert colors

Convert RGB artwork to CMYK before sending files to a print shop to avoid unexpected shifts in saturation or contrast.

Use CMYK to RGB conversion when you need a quick on-screen preview of a print-ready palette or when digitizing printed materials.

Manual conversion steps

To convert RGB to CMYK by hand, normalize each RGB value to a range between 0 and 1, find the largest value and compute the key (K).

  • K = 1 − max(R, G, B)
  • C = (1 − R − K) ÷ (1 − K)
  • M = (1 − G − K) ÷ (1 − K)
  • Y = (1 − B − K) ÷ (1 − K)

Multiply each value by 100 to get percentages. To return to RGB, divide all CMYK percentages by 100 and reverse the formula.