CMYK vs RGB: What Every Business Owner Must Know Before Printing

You approve a design on screen, send it to print — and the colours come back looking dull, muddy, or completely different from what you saw. This is one of the most common (and most avoidable) mistakes in print design, and it almost always comes down to one thing: colour mode.

1. What Is RGB?

RGB (Red, Green, Blue) is a light-based colour model used by screens — phones, monitors, TVs. Colours are created by mixing light, and combining all three at full intensity produces white. RGB has a much wider colour range, which is why on-screen colours can look so vivid.

2. What Is CMYK?

CMYK (Cyan, Magenta, Yellow, Black) is an ink-based colour model used for printing. Instead of light, colours are created by layering ink on paper, and combining all four at full intensity produces black. CMYK has a smaller colour range than RGB — some bright screen colours simply cannot be reproduced with ink.

3. Why Print Colours Look Different From Screen

Because RGB can display colours that CMYK physically cannot print, any file designed in RGB and sent straight to a printer gets automatically converted — often producing duller, shifted, or unpredictable results, especially in bright blues, neon greens, and vivid oranges.

What you see on screen is a preview, not a guarantee — unless the file is built for print from the start.

4. Preparing Files Correctly for Print

• Set your design software's colour mode to CMYK before you start designing, not after
• Use a resolution of at least 300 DPI for anything that will be printed
• Include 3mm of bleed on all sides so trimming doesn't leave white edges
• Convert fonts to outlines/curves before sending final print files

5. Common Mistakes to Avoid

The most frequent print disasters we see: designing entirely in RGB, using pure black (0,0,0) for large text areas (which prints flat and lifeless — rich black is better for large dark areas), and skipping bleed, which results in visible white borders after trimming.