What's the difference between Lap and Split time?

Lap time records the duration of the current lap only — it resets to zero after each lap recording. Split time is the total accumulated time from the start, useful for checking your cumulative progress at checkpoints.

How accurate is this timer?

This chronograph has 1-millisecond (0.001s) precision. It uses the browser's high-resolution performance.now() API, which is more accurate than traditional Date objects for precise timing needs.

Can I export my lap times?

Yes. After finishing your session, click the "Export CSV" button to download all lap times as a CSV file for further analysis in Excel or other spreadsheet software.

Does the timer keep running in the background?

Yes. The timer continues running even when you switch browser tabs or lock your phone screen. When you return, the time will be accurate — perfect for long sports sessions.

How are fastest/slowest laps calculated?

The system automatically compares all recorded lap times to find the shortest (fastest lap) and longest (slowest lap), highlighting both. Average pace is the arithmetic mean of all lap times.

Is my data stored on a server?

No. This tool runs entirely in your browser. All timing data stays on the current page and is never uploaded to any server, ensuring your privacy.

Online Chronograph - Precision Lap Timer

Home › Chronograph

00:00.000

Ready

📋 Lap Records

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Click "Start" to begin timing, then press "Lap" to record each lap

⏱️ Online Chronograph

📈 Statistics

📋 Lap Records