Online Stopwatch and Countdown Timer

Stopwatch and Timer gives you both halves of everyday timing in one page. The stopwatch counts up from zero to hundredths of a second and records lap times, with each lap showing both its own duration and the total elapsed when it was taken. The countdown timer counts down from a duration you set and sounds an alarm when it reaches zero.

Timing is based on the system clock rather than on counting intervals, so the elapsed time stays accurate even if the browser throttles the page in a background tab. A naive timer that simply adds ten milliseconds per tick drifts badly when a tab loses focus, which is exactly when you are least likely to notice.

Preset buttons cover the common durations, including the twenty-five minute focus block people use for the Pomodoro technique. The alarm is generated by your browser's audio engine, so there is no file to download and nothing to load when the timer finishes.

• Stopwatch accurate to hundredths of a second
• Lap times showing both split and total
• Countdown timer with hours, minutes and seconds
• Preset durations including a 25 minute focus block
• Audible alarm generated in the browser, with no file to load
• Remaining time shown in the page title
• Clock-based timing that does not drift in a background tab
• Keyboard friendly start, stop and reset

The stopwatch and timer is used by writers, developers, students, marketers and anyone else who needs the job done once without installing software. Common cases include:

• Timing a workout, a run or a set of intervals
• Running a focus block while working
• Timing a presentation or a speaking slot
• Counting down a cooking step
• Recording lap times in training