What is the average human reaction time?

It depends on the instrument. On a browser click test, Human Benchmark publishes a median of 273 ms and a mean of 284 ms across its aggregate results. Laboratory studies read faster: the Clemson University literature review by Robert J. Kosinski cites Laming (1968), who reported simple reaction times averaging 220 ms, because dedicated response hardware removes most of the screen and input latency a browser test includes.

Why is my score slower than the numbers I read about?

Usually because the faster numbers came from laboratory equipment. A browser test also measures your display, your mouse or touchscreen, and the browser itself. A 60 Hz screen only redraws every 16.7 ms, and input hardware adds its own delay on top, so the same person will read slower in a browser than in a lab.

Benchmarks

Average Reaction Time

Q: Does reaction time slow with age?

Not evenly. Der and Deary analysed reaction time data for 7,130 adults in the United Kingdom Health and Lifestyle Survey (Psychology and Aging, 2006) and found that simple reaction time changes little until around age 50, while choice reaction time slows steadily across the whole adult range. Differences between individuals at any age remain large.

Human Benchmark's published median for a browser click test is 273 ms. Here is the full distribution, where that number comes from, and where your score fits.

Test your reaction time All tests

Visual reaction time percentiles (five-attempt median)
Median time	Percentile	What it means
≤ 170 ms	top 1%	Elite — esports / sprinter territory
≤ 200 ms	top 5%	Very fast
≤ 225 ms	top 15%	Fast
≤ 250 ms	top 32%	Quick
≈ 275 ms	median	Typical
≥ 300 ms	bottom 33%	A little slow — very trainable
≥ 350 ms	bottom 15%	Slow — check sleep, screen, input lag
≥ 450 ms	bottom 5%	Recheck your setup before your reflexes

This is the reference curve your score is graded against on this site. Its median anchor sits within a couple of milliseconds of the 273 ms median Human Benchmark publishes for its own browser test; the percentiles between anchors are interpolated, not measured. As this site collects enough anonymous results, these curves will be replaced with first-party distributions, split by device. Sources for every figure on this page are below.

Where these numbers come from

There is no single “average human reaction time”, because the answer depends on what the stopwatch is attached to. Rather than invent a house figure, this page names its sources. Every millisecond quoted below is attributed.

Browser click tests

According to Human Benchmark, which publishes aggregate statistics for its own reaction time test, the median result is 273 ms and the mean is 284 ms, drawn from tens of millions of recorded clicks. That is the closest public comparison to what you get here, because it is the same kind of measurement: an ordinary browser, a real screen, and a consumer mouse or touchscreen.

Laboratory studies

Lab figures are faster. In A Literature Review on Reaction Time by Robert J. Kosinski of Clemson University, the long-accepted means for college-age participants are about 190 ms for a light stimulus and about 160 ms for a sound. The same review cites Laming (1968), who reported that simple reaction times averaged 220 ms while recognition reaction times averaged 384 ms — working out what you saw costs far more time than merely noticing that something happened. That gap is exactly what the choice reaction test makes you feel.

Large population samples

For how the number moves over a lifetime, the useful reference is Der and Deary, who analysed reaction time data for 7,130 adults in the United Kingdom Health and Lifestyle Survey (Psychology and Aging, 2006). They found that simple reaction time changes little until around age 50, while choice reaction time slows steadily across the whole adult range.

Device and browser latency

A browser test never measures your nervous system on its own. It measures your nervous system plus every source of latency between the signal and the recorded click:

Display latency — a 60 Hz screen only redraws every 16.7 ms, so the green state can exist in memory for most of a frame before your eyes can possibly see it. Panel response time and any television-style image processing add more.
Input latency — mice, trackpads, wireless receivers, and touchscreens each sample and report at their own rate.
Browser and system latency — event dispatch, compositing, and whatever else the machine is busy with all add small, variable delays.

Human Benchmark notes the same limitation about its own test: the result is affected by the latency of your computer and monitor. Added up, this overhead is worth tens of milliseconds and differs from device to device, which has two practical consequences. Your score is a fair comparison against yourself on the same device. It is not an exact comparison against a score from a different site, browser, or machine — a difference of a few milliseconds between two setups says more about the hardware than the people.

That is why this site scores the median of five attempts rather than your luckiest single click, and tracks mobile and desktop bests separately.

What actually moves your reaction time

Alertness — sleep loss, alcohol, and circadian lows all slow people down; caffeine buys some of it back.
Age — per Der and Deary above, simple reaction time holds up well until around 50, while choice reaction time drifts upward throughout adulthood.
Practice — the first few runs improve rapidly as the task becomes automatic; after that, gains are small but real.
Hardware — high-refresh monitors, wired mice, and low-latency audio all shave off part of the overhead described above.

For a plain-English read on what counts as good, great, and elite, see what is a good reaction time.

Want the decision-speed version of this number? Take the choice reaction test, or swap your eyes for your ears with the audio reaction test.