Stopwatch
A precise online stopwatch with lap times — hundredths of a second, a lap table with lap and total times, and pause/resume.
A big, readable stopwatch for workouts, cooking, speed tests, and classroom timing. Times are measured against your device's real clock (not by counting ticks), so the reading stays accurate even if the display hiccups. Record laps as you go and compare lap times against totals in the table.
00:00.00
Ready
How to use this calculator
- Press Start to begin timing.
- Press Lap at each split you want to record — the lap appears in the table instantly.
- Press Pause to freeze the clock, Resume to continue.
- Press Reset to clear the time and all laps back to zero.
The formula
Elapsed time = current clock time − start time (+ any banked time from before a pause). Displayed as minutes:seconds.hundredths, with an hours figure past 60 minutes.
Worked example
Time a 1 minute 1.23 second test and the display reads 01:01.23 — the formatter turns 61,234 milliseconds into minutes, seconds, and hundredths exactly. Race two 30-second heats with a lap in between and the table shows lap 1 at 30.00, lap 2 at 30.00, total 1:00.00.
Frequently Asked Questions
How accurate is this stopwatch?
Elapsed time is calculated from your device's system clock every time the display refreshes, not by adding up timer ticks, so it does not drift the way naive counters do. The display refreshes about 30 times a second and shows hundredths — plenty for workouts, cooking, and games; sanctioned sports timing still needs dedicated equipment.
How do laps work?
Press Lap while the stopwatch runs (or while paused after a run) and the table records the lap number, that lap's own time, and the total elapsed time at that moment. Laps are listed newest-first so the latest split is always at the top, and Reset clears everything.
Does pausing lose time?
No. Pausing freezes the accumulated total, and resuming continues from exactly that figure. The math stores the banked time plus the current run segment, so pause and resume as often as you like — the total stays the same as one continuous run would give, minus the paused gaps.
Will it keep time if I switch tabs?
Yes. Because the reading always comes from the clock rather than from counting screen updates, a background tab that refreshes slowly still shows the correct elapsed time when you come back to it. Only closing the page ends the session.
What's the difference between a stopwatch and the online timer?
A stopwatch counts up from zero to measure how long something takes; a countdown timer counts down from a set time to tell you when to stop. Use the stopwatch for laps, runs, and experiments, and the Online Timer for tea, Pomodoro sessions, and anything with a fixed duration.