Time anything from a workout interval to a Rubik’s cube solve with this online stopwatch. It counts up to a hundredth of a second and lets you record lap and split times while it keeps running — no app, no sign-up.
How it works
When you press Start, the stopwatch records the current timestamp from your device clock. The elapsed time it shows is simply now minus that start time, so it tracks real elapsed time rather than counting ticks. That means the count stays accurate even if the tab is in the background or the page briefly lags. Stop pauses by freezing the elapsed value; Start again resumes from where you left off. Pressing Lap captures a snapshot of the current elapsed time (the split) and records the gap since the previous lap (the lap time) without stopping the clock.
Lap time vs. split time — the distinction that matters
These two terms are sometimes used interchangeably but mean different things:
- Split time (cumulative): The total elapsed time from the very beginning to the moment you pressed Lap. Useful for knowing exactly where you were at each checkpoint.
- Lap time (segment): The time for that individual segment only — the difference between consecutive splits. Useful for comparing pace across segments.
For example, if your split times are 1:32, 3:07, and 4:41, your lap times are 1:32, 1:35, and 1:34 — the second and third laps were about 3 seconds slower than the first. Both pieces of information are shown for each lap in the table.
Common use cases
Track and field / running intervals: Tap Lap at the end of each 400m or mile to record each segment without stopping the overall count. Compare lap times to identify where your pace drifted.
Speedcubing (Rubik’s cube solving): The stopwatch is accurate to a hundredth of a second, which is the standard precision for competitive solving. Use Lap to separate inspection time from solve time if timing two phases.
Study sessions with the Pomodoro method: Start the stopwatch when you begin a work block, lap at each break, and review the lap table to see how much time you actually spent focused versus on break.
Cooking: Time multiple parallel items with laps — pasta starts at 0:00, sauce goes in at 3:45 (lap), plating happens at 12:30 (lap). The lap table gives you a timeline of your cooking sequence.
Sports drills: Lap at the end of each sprint, push-up set, or drill rep to track performance over a session.
Worked example
You run four 400-metre laps and tap Lap at the end of each:
| Lap | Lap time | Split (total) |
|---|---|---|
| 1 | 1:32.40 | 1:32.40 |
| 2 | 1:35.10 | 3:07.50 |
| 3 | 1:33.80 | 4:41.30 |
| 4 | 1:30.05 | 6:11.35 |
The split column shows the running total; the lap column shows each segment on its own, making your fastest and slowest laps immediately obvious (lap 4 was fastest at 1:30, lap 2 was slowest at 1:35). Reset clears the time and all laps.
Accuracy notes
The stopwatch uses the browser’s high-resolution time API and displays to a hundredth of a second. For most practical uses this is sufficient. The display renders on screen roughly every 50–100ms, so the shown value may briefly lag by a frame — the underlying elapsed time calculation is not affected. Everything runs locally in your browser, with nothing uploaded.