Reaction Time Test

How this test works

Press Start test and the screen turns red. After a random wait of between 2 and 5 seconds it turns green, and you respond as fast as you can: click it, tap it, or press Space or Enter. The wait is different every round, so there is no rhythm to learn.

There are 5 rounds. After each one you see that round's time, and the next round starts when you are ready. If you respond while the screen is still red, that round shows Too soon, doesn't count, and starts again with a new wait. If you switch to another tab mid-round, the round is dropped too: browsers slow down timers in background tabs, so a time from that round would be wrong.

How we calculate your result

The clock starts in the animation frame in which your browser draws the green screen, using the browser's high-resolution timer (performance.now()). It stops at the timestamp the browser attaches to your input the moment it receives it. For a mouse or a finger that is when the button or the screen is pressed down, not when you let go, so the time your finger spends on the way back up is never counted.

Your result is the average (mean) of the 5 rounds, rounded to the nearest millisecond. The fastest and slowest rounds and every individual time are shown with it, so you can see whether one round pulled the average up. All of the timing and the calculation happen in your browser.

Is my reaction time good?

A typical result on a test like this is about 273 ms. That figure is the median of over 81 million clicks on Human Benchmark's reaction time test, which, like ours, times a click on a screen that turns green and averages five tries. Your average is rated against it using five bands of our own, set so that 273 ms falls in the middle one:

These are One Quick Try's bands, not an official or medical scale, and the typical figure comes from another site's visitors, not from ours: we don't store anyone's results. Human Benchmark itself notes that a computer can add 10 to 50 ms to every click, so the same person can land in different bands on different devices.

What can change your result

Part of every result is your device, not you. A browser test cannot separate the two, so it helps to know where the extra time comes from:

• The display. A screen only shows a new picture when it refreshes. At 60 Hz that is every 16.7 ms, so the green can reach your eyes up to one refresh after the browser draws it. A 120 Hz or 144 Hz screen refreshes more than twice as often, which shortens that wait.
• The input device. Mice and keyboards report to the computer at fixed intervals, and wireless and Bluetooth devices can add a little more. Touchscreens scan for touches on their own schedule, and many phones spend extra time deciding whether a touch is a tap or the start of a scroll.
• How busy the device is. Heavy tabs, a video playing in the background or a battery saver mode can make the browser slower to draw the change and slower to notice your press.
• You. Tiredness, distraction and where your hand starts all show up in the number.

How to get a consistent result

• Use the same device and the same way of responding every time. Mouse, keyboard and touch results are not interchangeable.
• Rest your finger on the mouse button, the Space bar or just above the screen before the round starts.
• Close other heavy tabs, and plug a laptop in so it isn't saving power.
• Look at the middle of the screen rather than at the edges or the round counter.
• Compare complete runs with each other, not single rounds. One run of 5 tells you more than your best single click.

How can you improve your reaction time?

Mostly by removing what slows you down. Practice the exact response you are tested on, be alert and rested, keep your finger ready, and cut the delay your equipment adds. Your results usually improve over the first few runs as the task becomes familiar.

• Practice the same task. The same key or button, the same hand, the same device.
• Be alert. Tiredness and distraction make reactions slower and more uneven.
• Get ready. Rest your finger on the button and look at the middle of the box before each round.
• Cut device delay. A higher refresh rate, a wired mouse or keyboard and a TV's game mode all make the green reach you sooner.
• Don't guess. Pressing early gives "Too soon" and restarts the round.

Getting faster here makes you faster at this test. It isn't evidence of faster reactions anywhere else, such as behind the wheel.

What this test does not measure

This measures simple visual reaction time on your device: the time between the browser drawing a change and the browser receiving your response, including your screen's and input device's own delays. Because those delays differ from device to device, your result is best compared with your own earlier results on the same setup.

It is not a medical or psychological assessment, it says nothing about intelligence, and it is not a test of whether you are fit to drive or to do any other task.

Want a harder version? The Choice Reaction Time Test adds a decision: four squares, and you have to hit the right one. To react to sound instead of color, try the Audio Reaction Time Test.