Colour blindness · free

I will check whether the creative reads with colour blindness

A red price on green passes normal contrast but merges for one man in twelve. I recompute the contrast with the Machado model.

Image
Drop a card or a bannerJPG, PNG, WEBP or GIF up to 10 MB
Show me an image — I will check “Colour blindness”. This result comes first, 12 more checks are in the same report.

How I check

  • I take the letter and background colours by pixels for every text block.
  • I convert them for protanopia and deuteranopia (Machado, 2009) and compute the WCAG contrast again.
  • A fail if the headline, price or button drops below the norm.

Common mistakes

  • Red and green of the same lightness for “before/after”.
  • A discount marked only by colour, without size or a plate.

FAQ

How do I fix it?

Separate text and background by lightness: light on dark. The hue can stay, but the lightness must differ.