According to World Atlas, the distribution of eye color around the world is as follows:
Brown: 70 to 79% of the world’s population has brown eyes. Eye color is partially genetic, and if one of your parents has brown eyes, then you will probably have brown eyes. Eye color is also related to the amount of melanin in your skin. The more melanin you have in your skin, the darker brown your eyes will be.
Blue: 8 to 10%. Blue eyes color is thought to have resulted from a genetic mutation somewhere between 6,000 to 10,000 years ago. If you are blue-eyed, then you and other blue-eyed people have a common ancestor.
Hazel: 5%. This eye color, which is a mixture of green and brown/orange/gold, occurs most frequently in North Africa, the Middle East, Brazil, and Spanish-speaking countries. Depending on the lighting and what the person is wearing, hazel eyes can appear to change color.
Amber: 5%. This eye color is light brown, copper, or rusty and may appear yellowish. Amber eyes are more common in Asia, South American, and South Africa. Amber eyes are more common among animals like wolves, dogs, cats, owls, and eagles.
Gray: 3%. Gray eyes are rare and result from no melanin present in the iris along with extra amounts of collagen, which blocks the bluish hues from emerging. Because of the lack of melanin, gray eyes are most common among lighter-skinned people.
Green: 2%. Green eyes are very rare except in Scotland and Ireland, where 86% of the population has either green or blue eyes. No one is born with green eyes. They develop around the age of six months.
Violet or red eyes: <1%. These exceedingly rare eye colors are caused by a lack of pigmentation in the iris (violet coloring) or by albinoism (red coloring). The eyes may appear violet or red because the lack of pigmentation allows the blood vessels to be seen, and that will appear either violet or red. Some albinos have very light blue eyes, but in the most extreme forms of albinoism, the eyes will appear red.
Heterochromia: <1%. A very rare medical condition can cause people to have two different eye colors within one or both eyes, or cause one eye to be a different color than the other eye. Heterochromia is more common among dogs with lighter hair coloring on their heads and is particularly notable in huskies, dalmatians, and Australian shepherds.
Up to 16 genes determine eye color, and children’s eyes may change color as they grow. For example, in dark-skinned people, the amount of melanin present in their irises at birth is often less than the amount of melanin they will eventually have, and as their irises receive more melanin, they will turn browner.