Basic Calculator
2,458 + 369 × 7
5,041
Scientific Calculator
sin(30) × log(100) + √25
7.0000
Stopwatch
00:00:00.00
How to use the Stopwatch
Press Start to begin timing, use Lap to record an elapsed split, and press Reset to clear the stopwatch. It is useful for workouts, study sessions, experiments, tasks, and any activity where elapsed time matters.
What it solves and the timing method
The stopwatch measures elapsed time between a start event and the current or stopped event. The displayed time is built from elapsed intervals rather than from a fixed clock time, making it suitable for measuring duration.
Science behind the stopwatch
Elapsed time is the difference between two time readings: Δt = tend − tstart. The display converts the measured interval into minutes, seconds, and hundredths of a second for readability; actual precision depends on the browser and device timing environment.
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