CMYK vs RGB: When Print Reality Bites Back

RGB and CMYK are not just different formats; they are different physics. RGB adds light (start at black, mix red+green+blue, end at white). CMYK subtracts light (start at white paper, mix cyan+magenta+yellow ink, end at near-black). Anything you can show in one but not the other is "out of gamut" - and your design ends up looking different.

The painful conversions

Pure RGB blue (#0000ff) turns muddy purple in CMYK. Print blues are always slightly desaturated.

Neon green (#00ff00) becomes a tired apple-green. Sustainable greens print well; neon greens do not.

Saturated orange (#ff5500) mostly survives - oranges are inside the printable gamut.

Pure black on screen (#000000) prints as a thin gray-black. Print designers use a "rich black" recipe (e.g. C60 M40 Y40 K100) for body blacks.

The rules that save you time

1. Convert early, not late

If a brand color absolutely has to look identical in print and on screen, pick it in CMYK first, convert to RGB second. The CMYK gamut is smaller, so this guarantees the color exists in both. The reverse process loses information.

2. Spot colors for critical brand assets

Pantone (PMS) colors are physical ink mixes, not CMYK simulations. If your brand red must be exact on every business card and shopping bag, ship a Pantone spec alongside the HEX/CMYK so the print shop matches it.

3. Always include K (black)

Pure CMY mixed gives a muddy brown, not black. Modern printers add black ink (K) for crisp text and shadows. Never spec a CMYK value with K=0 unless you mean it.

4. Trust your proof, not your screen

A printed proof from the actual press will tell you the truth. Even a calibrated screen on a perfect color profile is a forecast, not a guarantee.

The web designer's escape hatch

Most modern brand work lives 95% on screens. If your "print" is mostly business cards and t-shirts, design in OKLCH or P3 first, then sample down to CMYK only for the print deliverables. You get the punchier digital experience without sacrificing print legibility.

Convert any color across formats

Get HEX, RGB, HSL, OKLCH, and CMYK side by side - and a print-friendly fallback - in our Color Converter.