CMYK is a subtractive color model used in printing. The letters stand for cyan, magenta, yellow, and key, which is black. Printing starts with white paper. Each ink layer subtracts light. Cyan absorbs red. Magenta absorbs green. Yellow absorbs blue. Together they absorb most of the spectrum and produce dark colors. Black is added separately because mixing cyan, magenta, and yellow produces a muddy brown, not a true black. The K layer also saves ink and improves text sharpness.

CMYK is the opposite of RGB, which is additive. Screens emit light. Print reflects it. A color that looks vibrant on screen may look dull in print because the gamut differs. RGB can display colors that CMYK cannot reproduce. Neon greens and vivid oranges are common victims. Designers converting a file from RGB to CMYK often see the colors shift. The shift is unavoidable. The best practice is to design in CMYK from the start if the final output is print. If not, expect to adjust. Printers also use spot colors for exact matches. Pantone is the standard system. A brand might specify Pantone 185 C for its red. The printer mixes that exact ink rather than approximating it with CMYK. Spot colors cost more but ensure consistency. For most print jobs, CMYK is sufficient. For brand-critical colors, spot inks are worth the expense.

CMYK facts

• Subtractive — inks absorb light
• Four plates — cyan, magenta, yellow, black
• Smaller gamut — fewer colors than RGB
• Black added — for depth and text clarity
• Spot colors — exact matches for brand colors

CMYK is the language of printing presses. What you see on screen is not what you get on paper.