Online Stopwatch

Online Stopwatch with Lap Timer — Precise Browser-Based Timing for Any Activity

A reliable stopwatch is one of those tools you need occasionally but need instantly — during a workout interval, a presentation rehearsal, a cooking timer, a sports drill, or a productivity sprint. This browser-based stopwatch gives you centisecond precision, unlimited lap recording, and automatic fastest/slowest lap highlighting with no app download or sign-in required.

How to use this stopwatch

Click Start to begin timing. While the clock is running, click Lap to record a split time — the stopwatch keeps running and records the time elapsed since the last lap. Click Stop to pause the timer at any point and Resume to continue from where you paused. When you are done, click Reset to clear all laps and return to zero. The stopwatch automatically switches to hours:minutes:seconds format when timing exceeds 60 minutes, so it works for long-duration events like endurance runs or extended work sessions.

Lap analysis and performance tracking

When you have recorded two or more laps, the table below the timer highlights the fastest lap in green and the slowest lap in red. Summary cards show the best and worst split times at a glance. This is particularly useful for interval training where you want to see whether your pace is consistent across sets, or in competitive contexts like swim or track training where comparing split improvements across sessions matters. Each lap entry shows both the split time (time for that lap only) and the cumulative elapsed time.

Who uses this tool

Athletes and fitness enthusiasts use it for interval training, tracking rest periods between sets, and timing race simulations. Presenters and speakers use it to rehearse talks to specific time slots. Teachers use it for timed classroom activities and exam countdowns. Developers use it to manually benchmark how long a user task takes during usability testing. Coaches use it at practice sessions to record athlete split times without needing specialised sports equipment.

Privacy and data handling

This stopwatch runs entirely in your browser using JavaScript timers — no timing data, lap records, or session information is sent to any server. It works offline after the page loads.