Reaction Time Test
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Test your reaction time in milliseconds with five tries, and see how it compares with a published age-group study. Scores stay on your device.
Quick answer: A reaction time test measures the milliseconds between a signal and your response. In the Woods et al. 2015 lab study of 1,469 adults aged 18 to 65 the average simple visual reaction time was 230.8 ms. This test runs five tries, shows your average, median and best, and compares your average with that study's age groups. A browser test usually reads higher than a lab because of screen and mouse delay.
Finish five tries to see your average. Your result appears here.
Your average reaction time
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milliseconds (ms), mean of five tries
| Try | Time (ms) |
|---|
Convert a reaction time
Enter a reaction time to see the conversions.
Your results never leave your device. Saved bests live in this browser only, and your times are never sent to us or anyone else.
📐 Formula
Reaction time = the time of your press minus the time the green appeared, in milliseconds. Your average is the mean of five valid tries. Ruler drop distance = ½ × 9.80665 × t², and distance traveled = speed × time.
How to Use the Reaction Time Test
Choose click or spacebar
Pick click or tap, or spacebar. Each input keeps its own saved best. Choose an age group if you want a comparison.
Press the pad and wait for green
The pad turns red after you press it. Wait. It turns green after a random 1 to 3 seconds. Pressing early cancels that try and you start it again.
Press as soon as it turns green
Your time in milliseconds shows at once. Repeat until you have five valid tries.
Read your result
See your average, median, best, slowest and spread, how you sit against the age group, and what your time means as ruler drop and driving distance.
How does this reaction time test work?
Press the pad and it turns red. After a random wait of 1 to 3 seconds it turns green, and the clock starts when the green is drawn on your screen. Press as fast as you can and the milliseconds between the green and your press are your reaction time for that try. Do it five times. If you press while the pad is still red, that try does not count and you start it again.
The page shows each try, then your average (mean), median, best, slowest and spread. The median matters here: one early guess or one slow try can pull a five-try mean around, and the median ignores it. Timing uses your browser's high-resolution clock, and everything is scored on your device. Nothing is uploaded.
What is a good reaction time?
The most careful number we can point to is from a 2015 study by Woods and colleagues at the VA Northern California Health Care System. They tested 1,469 adults aged 18 to 65 on a simple visual task, with a bullseye appearing on screen and a mouse press as the response. The average was 230.8 ms. When the researchers corrected for their own display and mouse delay, it came to 213 ms. We compare you against the uncorrected figures, because your screen and mouse have delay too.
What is the average reaction time by age?
Reaction time gets a little slower with age. The study found about 0.55 ms more for each year of age, which is small: the gap between its youngest and oldest groups was about 21 ms. The table gives the study's group averages. The standard deviation shows how much people in the same group differed from each other. The study also found no significant difference between men and women.
| Age group | People | Average (ms) | Standard deviation (ms) |
|---|---|---|---|
| 18 to 24 | 86 | 217.9 | 19.5 |
| 25 to 31 | 115 | 221.0 | 22.8 |
| 32 to 38 | 201 | 224.8 | 23.4 |
| 39 to 45 | 273 | 227.7 | 26.6 |
| 46 to 51 | 276 | 233.6 | 27.2 |
| 51 to 58 | 272 | 236.4 | 27.0 |
| 59 to 65 | 246 | 239.1 | 28.1 |
| All adults | 1,469 | 230.8 | 26.8 |
The group labels are printed that way in the paper, including 51 in two groups. The table covers adults only, so it says nothing about the average reaction time of a 14 year old or any other child. The study also used a lab setup, so a score in your browser usually comes out higher. If yours does, that is not a sign something is wrong with you.
How accurate is an online reaction time test?
Accurate enough to track yourself, not to settle an argument. Three things sit between the color change and your result: how long your screen takes to show the green, how long your mouse or keyboard takes to report the press, and the browser. The Woods study measured the first two in its own lab and found they added about 17.8 ms on average (display 11.0 ms, mouse 6.8 ms). That figure belongs to their equipment. We do not subtract it from your score, because we cannot know yours.
What helps: use the same device and input each time, close other heavy tabs, and judge yourself on the median of five tries, not the single best. A wired mouse or a fast screen may read a few milliseconds lower, but we have not measured that, so treat it as a thing to try rather than a promise.
What is the difference between simple and choice reaction time?
This is a simple reaction time test: one signal, one response, so you never have to decide anything. A choice reaction time test has more than one possible signal, each with its own response, and the extra decision makes it slower. The age table above is for simple reaction time only, so do not compare a choice-test result with it. We have not built a choice test or an audio test. If there is one you want, say so on the contact page.
How do I take a reaction time test on a phone, keyboard or spacebar?
On a phone or tablet, choose click or tap and touch the pad. On a computer you can click or use the spacebar: select the pad with Tab or a click, then press the spacebar when it turns green. Each input is scored and saved separately, because a touchscreen, a mouse button and a key do not report presses with the same delay. If you want to know whether you are improving, stay on one input.
What does your time mean as a ruler drop?
The ruler drop test is the classic classroom version: someone drops a ruler and you catch it, and the distance it fell tells you your reaction time. It works because a falling object covers distance d = ½ g t² in time t, with g = 9.80665 m/s². Our arithmetic below turns a time into the centimeters a ruler falls before you catch it. The converter above does the same for any time you type in.
| Reaction time | Ruler falls (cm) |
|---|---|
| 150 ms | 11.0 |
| 200 ms | 19.6 |
| 250 ms | 30.6 |
| 300 ms | 44.1 |
| 350 ms | 60.1 |
How far do you travel during a reaction time?
Distance is speed times time. At 50 mph (22.35 m/s) a 250 ms reaction time is 5.6 m, about 18 ft, covered before you have started to respond. At 30 mph it is 3.4 m, and at 70 mph it is 7.8 m. These figures are our arithmetic from the numbers you enter, and they cover reaction time only. Real braking takes extra distance on top of it, and a real driver has more to see and decide than a green pad.
| Speed | Meters | Feet |
|---|---|---|
| 30 mph (48 km/h) | 3.4 | 11.0 |
| 50 mph (80 km/h) | 5.6 | 18.3 |
| 70 mph (113 km/h) | 7.8 | 25.7 |
What about gamers, F1 drivers, goalkeepers and tired or drunk reaction times?
People search for reaction times in all of these. We have not read a primary study for any of them that we would stand behind, so this page gives no figure for F1 drivers, goalkeepers, boxers, FPS players, or for the effect of lack of sleep or alcohol. Rather than guess, compare yourself with the adult table above and with your own saved bests, and if you are curious about sleep, the sleep debt calculator and how much sleep do I need pages are the place to start.
How can I improve my reaction time?
Do your five tries in one sitting while alert, with a finger resting on the button instead of hovering above it and your eyes on the middle of the pad. Expect your first try to run a little slower, and note that it still counts in your average. Your score will move a few milliseconds between sessions even if nothing changes, so a lower average across several days on the same device is the only evidence worth trusting.
Is reaction time the same as click speed?
No. Reaction time is one response to one signal. Click speed is how many clicks you can make in a fixed time. They train different things. For the second, see the click speed test, and for other browser-based checks see the online tests hub.
Is this reaction time test free?
Yes. It is free, needs no sign-up, and your results stay in your browser.
Frequently Asked Questions
Accurate enough to compare you with yourself, not to give a lab-grade number. A score from a laptop trackpad and one from a wired mouse can differ by more than the gap between two people of the same age. Pick one device and one input, and compare your median over several days.
Not by itself. The adult lab averages in our table run from about 218 to 239 ms, with a standard deviation of roughly 20 to 28 ms, and a browser adds screen and mouse delay on top. A 300 ms average is above those figures, but one session says little. Take five tries on a few different days before reading anything into it.
We do not give a figure. The study behind our age table tested adults aged 18 to 65, and we do not stretch its numbers to children. Take the test a few times on the same device and compare your own results over weeks.
Everyone's tries vary. In the Woods study the typical trial-to-trial standard deviation for one person was about 40 ms, around 17% of their average. That is why this page shows your median and spread next to the mean, and why one fast try tells you little.
Yes to both. On a phone, choose click or tap and touch the pad. On a computer, choose spacebar, select the pad and press the spacebar when it turns green. Each input is saved separately because a touchscreen, a mouse button and a key do not report presses with the same delay.
No. It cancels that try, shows "Too soon", and you start the try again. It is added to the too-soon count in your result so you can see how often you jumped the gun. The wait is random, between 1 and 3 seconds, so you cannot time it from a pattern.
Sources & Methodology
The age-group figures are from Woods DL, Wyma JM, Yund EW, Herron TJ, Reed B. "Factors influencing the latency of simple reaction time." Frontiers in Human Neuroscience 2015;9:131, doi 10.3389/fnhum.2015.00131, read November 12, 2026. We use Experiment 1 (1,469 adults aged 18 to 65), its uncorrected group means and standard deviations, the 0.55 ms per year age slope, the absence of a sex effect, and its measured 17.8 ms display and mouse delay (11.0 ms display, 6.8 ms mouse). The paper's text gives the youngest group as 217.8 ms and its table gives 217.9 ms; we show the table. Its lab used a bullseye stimulus and a mouse press, and the participants were not children. The ruler drop and distance figures are our arithmetic: d = ½ g t² with g = 9.80665 m/s², and distance = speed × time with 1 mph = 0.44704 m/s and 1 km/h = 1/3.6 m/s. Timing uses your browser's performance.now() clock, and all scoring runs on your device.