Set a countdown timer with hours, minutes, and seconds. Or use the stopwatch with lap tracking. Features keyboard shortcuts, drift-corrected timing, progress bar, and audio alert on completion.
00:00:00
Shortcuts: Space Start/Stop R Reset
Convert between Unix timestamps and human-readable dates.
Add/subtract dates or find the difference between two dates.
Convert times between timezones with a world clock.
Convert between metric and imperial length units.
Format, beautify, minify, and validate JSON with syntax highlighting.
Enter hours, minutes, and seconds in the input fields, then click "Start". The countdown displays as a large HH:MM:SS clock with a progress bar. When time runs out, an audio alert plays and a toast notification appears.
Press Space to start or stop the timer/stopwatch. Press R to reset. In stopwatch mode, press L to record a lap. These shortcuts work when you are not focused on an input field.
Click "Lap" or press L while the stopwatch is running. Each lap records both the split time (time since the previous lap) and the total elapsed time. Laps are shown in a scrollable list with the most recent at the top.
Yes. Instead of relying on setInterval alone (which can drift), the timer compares against Date.now() on every tick. This ensures accuracy even when the browser tab is throttled.
Yes. Because timing is based on Date.now() rather than counting intervals, the timer remains accurate even when the browser throttles the tab. The display updates as soon as you return.