Online stopwatch
Start, stop, reset and record lap times with tenth-of-a-second precision. It keeps counting even if you switch tabs.
Why it stays accurate in background tabs
When a tab goes into the background, browsers throttle internal timers to save battery, so a poorly built stopwatch "loses" seconds. This one doesn't count ticks one by one: it stores the moment you pressed Start and computes elapsed time as the difference between real timestamps. You can switch tabs, minimize the window or lock your phone's screen — when you come back, the time shown will still be correct.
How to use lap times (splits)
The "Lap" button records two values: the lap time (how long since the previous split) and the total time since the start. It's the classic way to time workouts: during track intervals, the lap time tells you whether you're holding your pace, while the total gives you a projection of your finish. It works just as well in the kitchen, for interval study sessions, or for timing the sections of a presentation — when you're done, copy all your splits with one click and paste them anywhere.