Stopwatch
Precise timing with lap tracking
00:00:00.00
Precise timing with lap tracking
Space Start/Stop · L Lap · R Reset · F Fullscreen
The ClockTools Stopwatch is a free, high-precision timing tool that runs entirely in your browser. It displays hours, minutes, seconds, and hundredths of a second, with lap tracking and split time recording. Use it for workouts, races, cooking, study sessions, productivity tracking, or any activity that requires accurate elapsed-time measurement.
Built on the browser's performance.now() API and rendered through requestAnimationFrame, this stopwatch delivers sub-millisecond internal precision with a smooth 60fps display update. The result is a responsive, drift-free timer that you can trust for accurate measurements - whether you are timing a 100-meter sprint or a 3-hour exam.
Press the Lap button at any point during a run to record a split time. The lap table shows each lap's individual duration alongside the cumulative total. Once you have recorded three or more laps, the stopwatch automatically highlights the fastest lap in green and the slowest in red, giving you instant insight into pacing consistency. This is especially useful for interval training, race splits, and repeated task measurements.
Click Copy to Clipboard to export your entire lap history as a formatted text table. Paste it into a spreadsheet, Slack message, training log, or email. No screenshots, no manual transcription - just clean, structured data ready for analysis.
Athletes and coaches use stopwatches for sprint times, interval training, and race pace analysis. Teachers use them to time student activities, quizzes, and science experiments. Professionals use them for benchmarking task completion times and tracking billable hours. Game night hosts use them for timed rounds and speed challenges. The full-screen mode makes the display readable from across a room, and keyboard shortcuts (Space to start/stop, L for lap) let you operate the stopwatch hands-free.