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Stopwatch & Lap Timer
Start, stop, and lap a precise stopwatch that actually keeps accurate time.
🟢 EasyDifficulty
1-1.5 hoursTime
Python, JavaScriptLanguages
What you're building
A real stopwatch with start/pause/reset controls and a lap button that records split times, showing each lap's duration and the gap from the previous lap — just like the stopwatch app on your phone, except you built the timing engine yourself and know exactly why it stays accurate.
What you'll unlock 🔓
You'll need
- Basic JavaScript
- A browser
🗺️ Build roadmap
01 Build the time display and control buttons
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02 Implement start/pause using setInterval
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03 Track elapsed time accurately with Date.now()
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04 Format milliseconds into MM:SS.ms
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05 Implement the reset button
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06 Add lap recording and a lap list
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07 Highlight fastest/slowest laps
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08 Polish with keyboard shortcuts
🔒
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