Stopwatch

Online Stopwatch with Lap Timer

A stopwatch measures elapsed time with centisecond precision — hundredths of a second — making it accurate enough for sports timing, interval training, and any task where precise duration matters. This online stopwatch works entirely in your browser with no installation required.

The lap feature lets you record split times without stopping the clock. Each lap shows the time for that interval alongside the cumulative total, so you can compare individual segments. The fastest lap is highlighted in green; the slowest in red.

Use Cases

• Running & cycling — Record lap splits for each km or mile, identify where you slowed down.
• HIIT & interval training — Time your work and rest intervals with precision.
• Cooking & baking — Time multiple dishes simultaneously using laps for each item.
• Productivity sprints — Measure focused work sessions using the Pomodoro technique or similar methods.
• Science & experiments — Record reaction times or procedure durations with centisecond accuracy.

How Lap Timing Works

Press Start to begin timing. While the stopwatch is running, press Lap to record a split — the clock keeps running uninterrupted. Each lap entry shows the time since the previous lap (the interval time) and the running total. Press Pause to freeze the display, then Resume to continue from where you stopped. Press Reset to clear everything and return to zero.