Reaction Time Test
How fast are your reflexes? Measure it in milliseconds.
Round
1 / 5
Average so far
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Your record
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on this device
Timing uses the browser’s high-resolution clock. Your display adds a few milliseconds of its own, so compare results against your own history rather than other people’s setups.
Private by design. This tool runs entirely in your browser. Your input is processed on your own device and is not uploaded by DO101.
About the Reaction Time Test
Wait for green, then click as fast as you can. DO101 measures your reaction time with high-resolution browser timing across five rounds and gives you an average you can compare and share.
How to use it
- 1Press start and wait for the screen to turn green.
- 2Click, tap or hit space the instant it changes.
- 3Repeat five times for your average.
What you get
- Five rounds with a running average
- High-resolution performance timing
- Too-soon detection
- Personal best saved locally
- Works with mouse, touch or keyboard
Frequently asked questions
What is a good reaction time?
Around 250 ms is typical for a visual click reaction. Under 200 ms is fast. Anything below about 100 ms usually means you anticipated the change rather than reacted to it.
Does my screen affect the result?
Yes. Display latency and refresh rate add a few milliseconds, so compare your scores against your own history rather than against other setups.
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