Apps like Reaction Time exist for one question people want answered right away: how fast are your reflexes, in actual milliseconds. We built Quickflash, a free reaction test that runs directly in your browser. Wait for the flash, tap as fast as you can, see your number. No install, no account, nothing between you and the result.
Play Quickflash now
Tap into the panel below, wait for it to turn blue, then tap again as fast as you can.
How it works
Tap the panel to arm a round. It turns red first, meaning wait, then flips to blue after a random delay of one and a half to four seconds. Tap the instant it flips and your reaction time shows up in milliseconds. Tap too early and the panel calls it a false start, a friendly retry rather than a bad score, since jumping the gun says nothing about your actual reflexes.
Quick test mode runs single rounds back to back so you can chase your personal best. Daily challenge mode locks in five rounds with the same delay sequence for every visitor that day, then averages your times so you can compare fairly against your own best average, day over day. Both your best single time and your best average live in your browser’s local storage, and a streak counter tracks how many days in a row you have shown up. On touch, tap the panel; on a keyboard, press space or enter.
How it compares to Reaction Time
Reaction Time goes well beyond what we built here. It logs a full history of every attempt, breaks results down with charts over weeks and months, includes multiple test types beyond a single visual cue, and keeps working fully offline once installed. It is built for someone tracking reflex training as an ongoing habit, not just checking a number once.
Quickflash keeps the one mechanic that makes reaction tests worth returning to: wait, react, see the number, try to beat it. We left out the long-term charts, the account, and the extra test modes. There is no history beyond your current best single time and best average, and no training program behind it.
If you want to settle an argument about who has faster reflexes, or you just want a thirty-second break between tasks, this covers it well. If you are seriously training reaction speed and want to see your progress charted over months, the full app’s history and multiple test types will get you there.
Get the full app
Reaction Time is free to download on Android and adds detailed history, charts, and additional test types beyond the daily challenge here.
Frequently asked questions
Is this the real Reaction Time app?
No. Quickflash is an original reaction test we built, inspired by the wait-and-tap idea behind Reaction Time. We are not affiliated with, endorsed by or connected to Banensoft or Reaction Time in any way. For detailed history and additional test types, download the official app using the link above.
How accurate is the millisecond reading?
Quickflash times the gap between the panel switching to blue and your tap using the browser’s high-resolution clock, the same approach most online reaction tests use. Real-world numbers depend on your device’s screen refresh rate and input lag, so treat the reading as a consistent way to track your own trend rather than a lab-grade measurement.
What happens if I tap too early?
The panel flags it clearly as a false start and lets you try again immediately. It does not record a fake time and does not count against your best score or your daily challenge average, since tapping before the cue tells you nothing about reaction speed.
Does everyone get the same daily challenge?
Yes. The five delay times in daily challenge mode are generated from the date itself, so everyone attempting that day’s challenge faces the identical sequence. Your average is then compared against your own personal best average, not against other players.
Is it free and does it work offline?
Yes to both. There is no signup and nothing to pay for. Once the page loads, the test is a single file with no outside requests, so it keeps working even if your connection drops. Your best times and streak are saved in your browser’s local storage on your device only.
Can I use this on my phone?
Yes. The panel is sized for touch and the layout adjusts down to small phone screens. On a keyboard, spacebar or enter works just as well as a tap.
