From HandWiki

Coloradd is a sign code for aiding color blind people to recognise colors, developed by Portuguese graphic designer and professor at the University of Minho, Miguel Neiva.[1] It consists of geometric shapes representing colors and color combinations. The app won the accessibility category of the 2013 Vodafone Foundation Mobile For Good Europe Awards.[2][3]


The code signs and color combinations

The code is based on five base signs: two triangles (one angled upwards and the other angled downwards), one diagonal line, one solid square box and one empty square box representing black, white and the primary colors: red (magenta), blue (cyan), and yellow. Colors derived from other colors have the symbols of the combined colors, creating derivative colors (orange, green, purple and brown) and dark or white tones. Metalized colors like silver or gold are shown with a left parenthesis on the symbols.

Uses and recognitions

Application of coloradd code in traffic lights with color blindness

Since its creation, Coloradd has been applied in various services, mainly in Portugal:

  • Hospitals: on patient wristbands, pill bottles and path lines[4]
  • Schools: Viarco coloring pencils[5][6] and students' note books[6]
  • Transports: subway maps,[7][8] traffic lights and parking lots[9]
  • Accessibility: paint cans, groceries, postage services,[9] energy monitoring[10]

It was also recognised by Buenos Aires University and TEDx Oporto.

In September 2017, Mattel launched a colorblind-friendly version of Uno that utilizes ColorADD.[11]


Further reading

External links