Reaction time test
The reaction time test measures, in milliseconds, how fast you click, tap or press Space when the box shows Now! No install needed.
Click or tap the area, or press Space or Enter. Tab moves to the buttons; Stop test ends the run.
Runs in your browser. Test data stays on your device.
- Average
- –Many people land around 200–300 ms
- Best round
- –Your fastest press in this run
- Rounds
- Round 1–
- Round 2–
- Round 3–
- Round 4–
- Round 5–
- Median
- –The middle time of the run
- Consistency
- –Spread between rounds; lower is steadier
- Personal best
- –Best 5-round average, saved only in this browser
What the time includes
Your screen, your mouse, touch screen or keyboard, and the browser each add a delay, so the time reads a little higher than your reflexes alone. Compare runs on the same device.
How to use the reaction time test
- Click Start reaction test. The reaction area appears and says Wait….
- Keep your eyes on the area and your finger ready on the mouse, the screen or the Space bar. Do not press yet.
- After a random wait of 1.5 to 5 seconds, the area changes to Now!, with a solid square and a new color. Click or tap the area, or press Space or Enter, as fast as you can.
- Your time in milliseconds appears. Press again for the next round. After five rounds you see your average, best round and median.
- Press New run to play again, or Stop test to end the run.
A press before Now! shows Too soon, and so does a press less than 100 ms after it. That round is not counted: press again to replay it after a new random wait. A mouse or finger press counts the moment you push down, not when you let go.
What the results mean
A run is five valid rounds, and every number is in milliseconds (ms).
| Result | What it means | What to do |
|---|---|---|
| Average of about 200 to 300 ms | The range many people land in on a test like this. A rough guide, not a pass mark. | Nothing to fix. Compare with your own earlier runs on the same device. |
| Average above 300 ms | Slower than that range. A tired or distracted run, or extra delay from your screen, input device or browser, can all cause it. | Rest for a moment and run again. Then go through the delays under “Times slower than expected”. |
| Best round far below the median | One press came much faster than the rest. | Trust the average and the median more than a single best round. |
| A large ± value in Consistency | Your rounds sit far from their average, for example after a distraction. | Run again with your attention on the area. The median moves less than the average when one round is slow. |
| Too soon: 1 or more | Presses before Now! and presses under 100 ms after it. They are not counted as rounds. | Wait for Now! before you press. |
| New best | The average of this run, in whole milliseconds, is lower than your saved personal best, or you had none yet. | Nothing to do. It is saved in this browser. |
Average is the mean of your five rounds. Best round is your fastest valid press. Median is the middle time of the five, so one slow round hardly moves it. Consistency is the standard deviation of the five rounds, shown as ± milliseconds, and lower means steadier. It appears once you have two rounds. In the rounds list, each bar fills up to 600 ms.
Personal best is the lowest five-round average you have reached, in whole milliseconds. It is stored in this browser’s local storage and goes nowhere else, so another browser or device starts empty. The test measures a button press against a screen. It is not a medical test.
Reaction time test not working?
The reaction time test asks for no permission, so it has few ways to fail.
Your browser does not support this test
The test needs pointer events, which current versions of Chrome, Edge, Firefox and Safari have. Update your browser or open the page in one of them.
A click or key press does not count
- Mouse and touch: only the main mouse button, the first finger or a pen counts. Right and middle clicks and a second finger are ignored.
- Keyboard: Space and Enter count while the focus is on the reaction area or on the page itself. After you move to a button with Tab, they press that button instead, so click the reaction area to bring the focus back. That click counts as a press.
- Combinations: a key pressed with Ctrl, Alt or Cmd is left to the browser. A key you hold down counts once.
The run stopped by itself
A hidden tab gets no animation frames, so the test cannot time a round there. It stops the run when you switch to another tab or leave the page. Press Start reaction test again and keep the tab visible.
Times slower than expected
The test times the gap between the frame in which the browser draws Now! and your press, so the time also includes the delay of your equipment:
- Screen: a 60 Hz screen draws a new picture every 16.7 ms and a 144 Hz screen every 6.9 ms, so a faster screen can show Now! a few milliseconds sooner. TV picture modes add more delay, so switch on game mode if your screen has one.
- Mouse, keyboard or touch screen: Bluetooth, power saving and a low polling rate can add delay, while a cable or a 2.4 GHz USB receiver usually adds little. Try a wired mouse for comparison.
- Browser and system: busy tabs, other programs and battery saver modes slow the page. Chrome’s Energy Saver and Low Power Mode on an iPhone can limit pages to about 30 frames per second, which slows how quickly the signal reaches your eyes. Close heavy tabs and plug in your laptop.
I cannot tell when it changes
The signal is more than a color: the dashed square and Wait… become a solid square and Now!, and screen readers announce Now!. The area has no animation, so a reduce-motion setting in your system changes nothing. If a night light or color filter hides the new color, go by the shape and the words, or turn the filter off for the test.
The personal best is missing
The best average is stored in this browser’s local storage. A private window, blocked site data or cleared site data leaves nothing to show on your next visit, and another browser or device has its own. A run that is slower than your saved best leaves it unchanged.
How we measure
The test shows the signal inside an animation frame (requestAnimationFrame) and takes that frame’s timestamp as the moment the signal appeared. It subtracts that moment from the timestamp of your press, which the browser records when the input happens, on the same clock; if the timestamp is missing or impossible, the time of the call is used. The wait before each signal is random, between 1.5 and 5 seconds, a press before the signal or under 100 ms after it is not counted, and a run is five valid rounds, summarized by the mean, the median and the standard deviation. The time still includes the delay of your screen, your mouse, keyboard or touch screen and your system, which a browser cannot measure, so compare runs on one device.
Frequently asked questions
What is a normal reaction time on this test?
Many people land around 200 to 300 ms. That is a rough guide, not a pass mark, and the page shows it beside your average. Your screen, your mouse, keyboard or touch screen and the browser add their own delay, so compare runs on the same device. The test is not a medical test and says nothing about fitness to drive.
Why does the test say I pressed too soon?
Because you pressed before Now! appeared, or less than 100 ms after it. Studies of reaction time commonly treat anything under 100 ms as a guess made before the signal could be seen, and the test does the same. The round does not count. Press again to replay it after a new random wait of 1.5 to 5 seconds.
Why are my times different on my phone and my computer?
The touch screen or mouse, the display and the browser each add their own delay, so every device gives slightly different numbers. A wired mouse on a fast screen often reads lower than a touch screen. Compare runs on the same device, with the same settings, rather than across devices.
What is a good reaction time for gaming?
There is no figure to aim for, and this test cannot say what is enough for a particular game. Your screen, mouse or keyboard and browser add their own delay here, and a game setup has another. Use the test to compare your own runs on one device, for example before and after you change a mouse, a cable or a screen setting, and keep everything else the same.
Can I take the test with a keyboard or a screen reader?
Yes. Press Space or Enter to react, and Tab to reach the buttons. The signal is not only a color change, because a solid square and the word Now! replace the dashed square and the word Wait. Screen readers announce Now! at once, though speech adds its own delay to the time you press.