ストップウォッチ

How to use

1. Click Start to begin timing. The display counts up in minutes, seconds, and hundredths.
2. Click Lap to record a split time without stopping the clock. Each lap shows its duration and running total.
3. Click Reset to clear all times, or Export CSV to download your lap data.

Related tools

• Pomodoro Timer
• Countdown Timer
• Date Difference

よくある質問

Is this stopwatch free?

Yes, completely free with no signup and no usage limits.

Does it send any data to a server?

No. Everything runs in your browser — your lap times never leave your device.

Does it work on mobile?

Yes. Works in Safari, Chrome, and Firefox on iOS and Android with large touch-friendly buttons.