Grab a mirror or open your phone's front camera, go near a window and zoom right in. Daylight shows your true colour; indoor light makes most eyes look darker. Match what you actually see, not what your passport says.
Choose the iris that looks most like yours. If you are torn between two, choose the one that covers more of your iris.
Slide until the eye matches yours as closely as you can.
Pick a colour first.
Four details most people have never checked. Zoom in on one eye.
Are your two eyes the same colour? Small differences in brightness don't count; we mean clearly different colours.
Pick the colour of your other eye.
Eye colour follows ancestry, not where you live now. We use this only to compare you with the right people. It stays on this device and is never sent to us.
Would you add your answers to our research? It is optional and anonymous, and your result appears either way.
There are no reliable population figures for these details, so they are not in your number. Every person who takes part helps us produce the first ones.