22 Mar 25 Eye-mazing Eye Facts

The human eye is a fascinating organ, second in complexity only to your brain. That’s why you can see clearly in both the bright, mid-day sunlight and also when you’re awakened suddenly from a deep sleep late at night. Without thinking about how you do it, your eyes focus immediately to show you what’s going on under every imaginable scenario. They’re truly “eye-mazing!”

Your eyes are able to focus in high resolution at an incredible range of distances — from mere inches before your face to miles across open water. And they can (and do!) respond incredibly quickly to keep you informed about what’s happening in your surroundings: From the instant a moving object enters your field of vision, it only takes 200 milliseconds for your eyes to perceive it and relay that information to the brain. Wow!

Here are 25 “eye-mazing” facts about your eyes:

1. Your eyes are the fastest muscle in the human body—able to adjust and perceive visual changes “in the blink of an eye.”
2. Though newborn babies cry, they can’t actually produce tears until around 6 weeks of age.
3. Approximately half of your brain is dedicated to the task of seeing and vision.
4. You can blink up to five times in a single second!
5. In an average year, you likely blink more than 5 million times (that’s about 17 blinks per minute).
6. Blue eyes look blue because they have less melanin than brown eyes, allowing collagen—which appears blue—to show through.
7. Your eyes are a biological supercomputer, able to perceive and process around 36,000 bits of information each hour.
8. Under the right nighttime conditions, your eyes can perceive the light from a single candle flame up to 14 miles away.
9. It is estimated that up to 80% of human memory is determined by what we’ve seen.
10. Human babies are born color-blind, and color perception begins to develop within about a week. At 6 months of age, a baby can see every color an adult can.
11. Most color-blind adults are male: 1 out of 12 men are color-blind, but only 1 out of 255 women are.
12. The human eye can detect up to 500 different shades of the color gray.
13. A healthy, normal human eye can perceive more than 10 million different colors.
14. A rare 2% of women with a specific genetic mutation of one extra retinal cone allows them to perceive more than 100 million colors. This condition is called tetrachromacy.
15. If a person is born with the ability to see and then goes blind, that person can still “see” their dreams.
16. Human eyelashes have a lifecycle of about 5 months.
17. The purpose of eyelashes is to keep dirt, sand, and other airborne debris from entering and damaging your eyes.
18. One of the most common eye injuries is poking yourself in the eyeball with your mascara wand. (Ouch! Stop doing that.)
19. Eyebrows have an important function: To keep sweat droplets from dripping into your eyes. And yes, they look great perched up there above your eyes, too.
20. Your eyes automatically close to protect you from what your brain perceives to be a danger—think of the last time somebody tossed something to you unexpectedly!
21. When reading on computer, tablet or phone screens, the human eye tends to blink less (which can result in tired, dry eyes).
22. Fewer than 1% of the population have a condition called heterochromia, where their eyes are two different colors. Mila Kunis is one of them.
23. Your eyes have about 7 million “cones” – the cells that enable you to perceive color and detail.
24. Your eyes also contain about 120 million “rods” – light-sensing cells that enable you to see in the dark. For comparison, cats have 6 to 8 times as many rods as humans do, giving them far superior night vision!
25. While your ears and nose continue to grow larger throughout your lifetime, your eyes remain the same size they were at birth. That’s why a baby’s eyes seem so adorably large.

Your eyes are truly amazing, aren’t they? We celebrate your eyes every day, and want to help support your vision for a lifetime of seeing your best.

Help us help you take great care of your eyes by scheduling your annual comprehensive eye appointment today!