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Colour blindness 0:43
A 43-second explainer of Colour blindness, narrated over the same demo you can try yourself.
Try the interactive Colour blindness demo
What this video covers
Colour blindness is reduced ability to tell certain colours apart - most commonly red from green - affecting a meaningful slice of people, mostly men. For design it means one thing above all: if colour is the only way you signal something, a lot of users simply won't receive the message.
Switch the simulation to red-green colour blindness and the "success" and "error" dots became the same muddy tone - the status you were relying on, gone. Add the tick, the cross and the words, and it read perfectly again. The colour was never the information; it was just one fragile way of carrying it.
