CMYK to RGB converter (and back)

Screens emit light in RGB (additive color); presses lay ink in CMYK (subtractive color). The RGB gamut is larger — vivid blues, greens, and oranges that a screen can display simply cannot be mixed from cyan, magenta, yellow, and black ink. When an RGB file converts to CMYK, out-of-gamut colors get pulled to the nearest printable color, which reads as "duller" or "muddier." Designing in CMYK (or soft-proofing against a CMYK profile) avoids the surprise.

No — this tool uses the standard naive formula, which is profile-agnostic. Real presses convert through ICC profiles (FOGRA39, GRACoL, SWOP) that account for ink, substrate, and dot gain, so the actual printed color shifts further. Treat this converter as a fast approximation for design decisions; rely on a color-managed proof for press-critical color.

Saturated RGB blues and purples (they shift toward muddy violet), bright greens (toward olive), vivid oranges, and anything neon. Pure RGB blue (0,0,255) is the classic example — it prints as a noticeably duller purple-blue. If a brand color lives in that range, specify a Pantone spot color instead of process CMYK.

For print-only work, design in CMYK from the start so what you see tracks what prints. For dual-use assets (web + print), design in RGB and soft-proof against your print profile before handoff. Web-to-print platforms like PrintIntegrator convert customer RGB uploads to press CMYK with an ICC profile at output time, which is more accurate than the naive formula.

Plain black is 100% K only — crisp for small text. Rich black layers other inks under the K (a common recipe is C60 M40 Y40 K100) for a deeper, denser black on large areas. Never use rich black for body text (registration shifts blur it) and never use plain black for large solids (it prints washed-out gray-black).