A simple, accurate online stopwatch with a built-in lap timer. Start, pause, and resume the clock, and tap Lap to record split times for workouts, races, cooking, study sessions, or any task you want to measure.
How it works
Elapsed time is read from the browser’s high-resolution performance clock rather than counted frame by frame, so it stays accurate to the millisecond even when the tab is in the background or the display is throttled. The readout shows minutes, seconds, and centiseconds (hundredths).
Each lap captures two numbers: the lap time (the duration of that segment alone) and the running total (elapsed time since start, also called the split). When you have more than one lap, the fastest is highlighted green with an up triangle and the slowest is marked with a down triangle.
Lap times vs split times — the difference explained
These two terms are often confused:
- Lap time is how long that specific segment took from the previous lap press to this one. It tells you your pace over that interval.
- Split time (running total) is the elapsed time from the very start to this lap press. It tells you where you are cumulatively.
For a runner, knowing your split tells you whether you are on target for a finish time. Knowing your lap tells you whether that last kilometre was faster or slower than the ones before it. Most coaches care about lap consistency; race strategy depends on splits.
Example — four 400 m laps
| Lap | Lap time | Running total | Note |
|---|---|---|---|
| 1 | 01:32.40 | 01:32.40 | |
| 2 | 01:35.10 | 03:07.50 | Slowest ▼ |
| 3 | 01:30.80 | 04:38.30 | Fastest ▲ |
| 4 | 01:33.00 | 06:11.30 |
Lap 3 is flagged as the fastest at 01:30.80, lap 2 as the slowest. The final split of 06:11.30 is the total time for all four laps.
Common uses
Athletics and fitness: Lap each interval in a workout to track pace consistency. Inconsistent laps — where the fastest and slowest differ significantly — point to pacing errors.
Cooking: Use the lap function to record when each component goes in, so you know the exact elapsed time for each step without stopping the clock between them.
Study sessions (Pomodoro variant): Press Lap at the end of each focus block instead of resetting, keeping a running log of your total focused time and how long each session actually ran.
Testing and benchmarking: Time repeated tasks and compare lap consistency — useful for manual timing of physical processes, presentations, or scripted events.
Everything runs locally in your browser; nothing is stored or uploaded. The time clears when you reset or leave the page.