You design a bright, vibrant flyer on your laptop, but the printed result comes out dull and darker than expected. The cause is almost always the same: the file was designed in RGB and printed in CMYK.

What is RGB?

RGB stands for Red, Green and Blue. It is the colour model used by screens, phones and cameras. Screens create colour by adding light together, which is why RGB can produce very bright, glowing colours.

What is CMYK?

CMYK stands for Cyan, Magenta, Yellow and Key (black). It is the colour model used by printers. Ink absorbs light rather than emitting it, so CMYK colours are naturally more muted than RGB colours.

Why colours shift when you print

Some RGB colours, especially bright neon blues, greens and purples, simply cannot be reproduced with CMYK ink. When the file is converted, those colours get mapped to the closest printable colour, which is why the result looks duller.

How to convert correctly

  • Convert your file to CMYK in your design software before exporting.
  • Ask for a proof if colour accuracy is critical.
  • Use a CMYK colour profile such as Coated FOGRA39 for commercial print.

As a rule of thumb: design in RGB only if the work will stay on screen. Anything going to print should be converted to CMYK first.