Scientists have recently identified gray as the rarest eye color, surpassing green, which was previously considered the rarest. Historically, the primary eye colors are brown, blue, hazel, and green, with green eyes long held as the rarest at about 2 percent of the global population. However, “recent scientific findings have introduced a new contender to the rarest eye color category.

Gray eyes were once considered a subset of blue, but recent studies reclassify them as a distinct color. “Scientists’ updated definitions now categorize gray eyes as a separate color distinct from blue.” This reclassification has shifted the hierarchy of eye color rarity, placing gray at the top.

According to VeryWell Health, brown eyes are the most prevalent, making up 55 to 79 percent of the global population. Blue eyes follow at 8 to 10 percent, and hazel eyes account for 10 percent. In the United States, blue eyes are more common than hazel, with 27 percent and 18 percent prevalence, respectively. Gray eyes, the newly identified rarest color, constitute less than 1 percent of both the U.S. and global populations.

Eye color is influenced by melanin, the pigment in the iris. “Higher melanin levels result in darker eyes, while lower levels lead to lighter eyes.” The specific hue is determined by different types of melanin, with eumelanin responsible for darker eyes and pheomelanin contributing to lighter shades like green or amber. Additionally, geographical location affects eye color, with lighter eyes and skin more common in regions farther from the equator.