Color Blindness Statistics: Prevalence by Gender, Type & Region

How Common Is Color Blindness?

Color blindness affects approximately 300 million people worldwide, making it one of the most common genetic conditions in humans. Roughly 8% of men and 0.5% of women of Northern European descent have some form of color vision deficiency. These numbers translate to about 1 in 12 men and 1 in 200 women globally. While the condition is rarely debilitating, it can have significant impacts on daily life, education, and certain career paths.

Prevalence by Gender

The stark difference in prevalence between men and women is due to the genetics of color vision. Red-green color blindness is inherited via the X chromosome, and since men have only one X chromosome (XY), a single defective gene is enough to cause the condition. Women have two X chromosomes (XX), so a functional gene on one chromosome can compensate for a defective gene on the other. This means women are far more likely to be carriers of color blindness than to be affected by it. Approximately 15% of women carry at least one gene for red-green color blindness.

Breakdown by Type: Red-Green Deficiencies

Red-green color blindness is by far the most common category, accounting for about 99% of all cases. Deuteranomaly, a reduced sensitivity to green light, is the single most prevalent type, affecting roughly 5% of men. Protanomaly, a reduced sensitivity to red light, affects about 1% of men. The more severe forms, deuteranopia (complete absence of green cones) and protanopia (complete absence of red cones), affect approximately 1.2% and 1% of men respectively. These types range from mild difficulty distinguishing certain shades to a complete inability to perceive red or green wavelengths.

Breakdown by Type: Blue-Yellow and Complete Color Blindness

Blue-yellow color blindness (tritanopia and tritanomaly) is far rarer than red-green types, affecting roughly 0.003% of the population regardless of gender. Unlike red-green deficiency, tritanopia is inherited through an autosomal chromosome (chromosome 7), so it affects men and women equally. Achromatopsia, or complete color blindness where a person sees only in shades of gray, is extremely rare at about 0.003% of the population. People with achromatopsia also typically experience light sensitivity and reduced visual acuity.

Regional and Ethnic Variations

Color blindness prevalence varies significantly across ethnic and geographic populations. People of Northern European descent have the highest rates, with up to 8% of men affected. Populations of Asian descent typically show rates of 4-5% in men, while those of African descent have the lowest reported rates at 2-4% in men. These differences are thought to result from different evolutionary pressures and genetic drift. Some isolated populations show notably different rates; for example, the island of Pingelap in Micronesia has an unusually high rate of achromatopsia at roughly 10% of the population, traced to a population bottleneck after a typhoon in 1775.

Total Global Impact

With a world population exceeding 8 billion, an estimated 300 million people live with some form of color vision deficiency. This is roughly equivalent to the entire population of the United States. The vast majority of these cases are mild to moderate red-green deficiencies that people learn to manage throughout their lives. Despite the large number of affected individuals, color blindness is still frequently overlooked in design, education, and public policy, leading to unnecessary barriers in daily activities.

Acquired Color Vision Deficiency

While most color blindness is inherited, it can also be acquired later in life. Conditions such as diabetes, multiple sclerosis, and macular degeneration can damage the retina or optic nerve, leading to changes in color perception. Certain medications, including some used to treat heart disease and psychiatric conditions, can also affect color vision. Age-related yellowing of the lens can reduce blue-yellow discrimination. Acquired color vision deficiency affects men and women equally and can sometimes be reversed if the underlying cause is treated.

Why Accurate Statistics Matter

Understanding the true prevalence of color blindness is essential for inclusive design, public health planning, and educational support. Many statistics cited online are based on older studies of limited populations, and global numbers are still estimates. Better data helps designers create accessible interfaces, helps schools identify and support affected students, and helps employers understand that color vision requirements may exclude a significant portion of the workforce. As genetic testing becomes more accessible, our understanding of color blindness prevalence continues to improve.

Frequently Asked Questions