Project
Roulette

Reaction Time Leaderboard

Click when it turns green, then argue about the results.

BeginnerWeb appGame5–12hAI-buildable 5/5no setupworth shipping

A reaction test with a shared leaderboard. Deceptively simple until you take the measurement seriously — display latency, early-click detection, and outlier rejection all matter if the numbers are going to mean anything.

UI
Logic
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Core features · 7

  • A target changes state after a randomised delay
  • Reaction time is measured and displayed
  • Clicking before the change is detected and rejected
  • A best-of-five run produces an average with outliers marked
  • Personal history is stored and charted
  • A shared leaderboard shows the best times
  • The randomised delay can't be learned or anticipated

The interesting part

  • Measuring accurately given display and input latency
  • Detecting anticipatory clicks rather than counting them as fast
  • Preventing trivially faked leaderboard submissions

Once it works

  • Add an audio-cue variant to compare modalities
  • Add a choice-reaction mode with multiple targets
  • Add a distribution chart of all attempts

Suggested stack

reacttypescripttailwindrechartssupabase

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