Date & Time

Online Timer & Stopwatch

Set a countdown timer with an alarm, or run a stopwatch that records laps to the hundredth of a second. Pick a preset for a quick 5- or 10-minute timer, or type an exact duration for workouts, cooking, study sprints, and presentations. Everything runs in your browser — the countdown stays accurate in a background tab and keeps counting wall-clock time even if your computer sleeps.

05:00

Duration

Presets

How to use the countdown timer

  1. Tap a preset — 5 min, 10 min, 25 min for a Pomodoro — or type the hours, minutes, and seconds you need.
  2. Press Start. The big readout counts down and the bar underneath fills as the time is spent.
  3. Pause stops the clock without losing your place; Reset puts the full duration back.
  4. When it reaches zero the display turns red and an alarm plays. Untick Alarm sound if you need a silent countdown.

Keyboard shortcuts: Space starts or pauses, R resets, and L records a lap in stopwatch mode.

Stopwatch with lap times

Switch to the Stopwatch tab to count up instead of down. Every press of Lap records a split alongside the running total, and the fastest and slowest laps are marked once you have at least two — useful for interval training, lap running, drills, and timing repeated tasks. Copy laps puts the whole table on your clipboard as tab-separated text, ready to paste into a spreadsheet.

Timer or stopwatch — which do you need?

A timer counts down from a duration you choose and alerts you at zero: use it when you know how long something should take, like a 3-minute egg, a 25-minute focus block, or a 5-minute speaking slot. A stopwatch counts up from zero with no end point: use it when you want to find out how long something takes, such as a lap, a workout set, or a support call.

Does the timer keep running if I switch tabs?

Yes. The countdown is calculated from the clock time you started it, not from counting frames, so a background tab that gets throttled still shows the correct time the moment you come back — and the alarm is scheduled separately so it fires even while the tab is hidden.

Is the timer accurate if my computer goes to sleep?

Yes. The tool reads wall-clock time rather than a monotonic frame counter, so ten minutes of sleep counts as ten minutes of countdown. When you wake the machine the display jumps to the correct remaining time, and a timer that expired while asleep is shown as finished.

How accurate is the online stopwatch?

The stopwatch records and displays hundredths of a second. Practical accuracy is limited by human reaction time on the start and stop presses, which is typically 150–250 milliseconds, so treat it as precise to roughly a quarter of a second for hand-timed events.

Can I link directly to a 5 minute timer?

Yes. Add a t parameter to the URL — for example /timer-stopwatch/?t=5m opens with five minutes preloaded. It accepts values like 90s, 5m, 1h30m, and 00:45, so you can bookmark the exact countdown you use most.

Why can't I hear the alarm?

Check that the Alarm sound box is ticked and that your device is not muted. Browsers only allow a page to play audio after you have interacted with it, so the alarm works because you pressed Start — but it will stay silent if the tab was reloaded and the timer resumed without a click.

Is any of my data sent to a server?

No. The timer, the stopwatch, and your lap times all run entirely in your browser with JavaScript. Nothing is uploaded, stored on a server, or shared, and the page works offline once it has loaded.

All Date & Time tools →