Online Stopwatch

This stopwatch runs right in your browser at hundredth-of-a-second precision — great for sports, study sessions, running laps, or any timed competition. Record laps and see your fastest and slowest splits highlighted automatically. No signup, no install.

It's useful well beyond sports timing. Teachers use it to run classroom activities, musicians time improvisation rounds, and anyone doing a manual test run can benchmark it easily. Because the fastest lap is highlighted green and the slowest red, you can spot outliers at a glance without doing any math.

The stopwatch uses your browser's most precise built-in clock, accurate to a hundredth of a second.

The main limitation of a browser stopwatch: if you close the tab or the browser crashes, your lap data is gone. We deliberately keep it in memory only, rather than saving it automatically, since silently storing timing data isn't something we want to do without asking first. If you want to keep your splits, copy them out or print the lap table before you close the page.

The lap feature is where this stopwatch is most useful day to day. Every time you press Lap, it records both the split — how long that one leg took — and the running total since you started. The fastest split turns green, the slowest turns red, so you can spot the outlier without scanning a column of numbers. Whether you're coaching a relay team, timing a production line, or just running intervals in the park, the color-coded lap table makes the numbers easy to read at a glance.

Official sports timing is far more precise than any browser tool, using electronic systems accurate to a thousandth of a second. This stopwatch measures to a hundredth of a second, which is plenty for training, coaching, and casual competitions — just not a substitute for certified race-timing equipment when an official record is on the line.