The fastest thing your body does all day
A blink is over in about a tenth of a second, yet you do it thousands of times a day. Each one spreads a fresh film of tears across the eye, clearing dust and keeping the surface smooth enough to see clearly. You barely notice because your brain quietly edits the moments of darkness out of your experience. The eye above blinks at the rate that matches what you are doing: fast while talking, slower while reading and slowest while staring at a screen.
Screens are the big variable. Studies of people reading on computers find their blink rate drops sharply, often by more than half, which is one reason a long day at a monitor leaves eyes dry and gritty. The slider lets you set your screen hours, and the totals change to match.
How we calculate it
We assume you are awake for about 16 hours a day. During those hours we use 17 blinks a minute for ordinary time and 7 a minute for screen time, so more screen hours means fewer blinks. Babies blink only two or three times a minute and children gradually speed up, so we use 3 a minute for the first year, 8 for ages one to five and 12 for six to twelve. The time with eyes shut multiplies the total by 0.15 seconds, a typical blink length.
| Situation | Typical blinks a minute |
|---|---|
| Newborn | 2 to 3 |
| Adult in conversation | 15 to 25 |
| Adult reading a book | about 10 |
| Adult on a screen | about 5 to 8 |
Worked example. An adult awake 16 hours with 6 hours of screen time blinks 10 hours × 60 × 17 = 10,200 times off-screen and 6 × 60 × 7 = 2,520 times on-screen, about 12,700 blinks a day. Over a year that is around 4.6 million blinks, with roughly 32 minutes of eyes-shut time a day.
Look after the blink
If your screen hours are high, the easiest fix is the 20-20-20 habit: every 20 minutes, look at something 20 feet away for 20 seconds. Many people find it brings their blinking back to normal and their eyes feel noticeably better by the end of the day.
Questions people ask
How often do people blink?
At rest and in conversation most adults blink around 15 to 20 times a minute. Babies blink far less, only a few times a minute, and the rate rises through childhood.
Why do screens make us blink less?
When we concentrate on reading or a screen, blinking can drop by more than half. That is one reason long screen sessions leave eyes feeling dry and tired.
How long does a blink last?
A typical blink lasts about a tenth to a sixth of a second. It is so quick that the brain fills the gap and we do not notice the world going dark.
What is the 20-20-20 rule?
A common tip for screen users: every 20 minutes, look at something about 20 feet (6 metres) away for 20 seconds. It gives your eyes a break and usually brings your blink rate back up.
Sources. Blink rates from Doughty (2001), Optometry and Vision Science; screen blink reduction from American Academy of Ophthalmology guidance. Calculations run in your browser; nothing you enter is sent anywhere.