Free tool · Life Events
Stopwatch / Countdown Timer
A simple stopwatch and countdown timer.
A stopwatch for timing how long something takes, with lap tracking, and a countdown timer that counts down from a time you set and alerts you when it finishes. Runs entirely in your browser tab with no account or app install needed.
- Nothing leaves your device
- Runs entirely in your browser
- Free, no account needed
How to use Stopwatch / Countdown Timer
Three steps, and nothing to install.
Choose stopwatch or countdown
Time something as it happens, or count down from a duration you set.
Record laps if you need them
The lap button captures split times while the stopwatch keeps running.
Keep the tab open
Leave the page open so the timer keeps running and the alert can fire.
More free tools
Free, private, and no sign-up on any of them.
How this works in your browser
Elapsed and remaining time are computed by comparing timestamps rather than by accumulating a count each tick. That distinction matters because browsers throttle timers in background tabs to save power: a tool that added up intervals would drift badly, while one that measures against the clock stays correct even when the display updates less often. The audible alert relies on browser audio, which requires prior interaction with the page before it will play. Nothing is stored between page loads, so a refresh resets everything, and on mobile the operating system may suspend a backgrounded tab entirely, which is why a native alarm is the safer choice for anything critical.
Stopwatch / Countdown Timer vs. typical online calculators
| Feature | Stopwatch / Countdown Timer (in-browser) | Typical online calculators |
|---|---|---|
| Where the maths runs | In your browser, on your device | Often posted to a server to compute |
| Your inputs are stored | Never - nothing is sent or saved | Frequently logged with your session |
| Works offline once loaded | Yes | No - needs a live connection |
| Ads inside the result area | None | Common on free calculators |
| Account required | No | Often, to save or export results |
| Usage limits | None - free, unlimited use | Sometimes capped per day |
Who uses Stopwatch / Countdown Timer
Timing work sessions
Track how long a task actually takes.
Exercise and intervals
Time rounds and rest periods with lap splits.
Cooking and short waits
Count down while you stay at the computer.
Presentations and practice
Keep a talk or rehearsal within its allotted time.
Frequently asked questions
What it can and cannot do, and what happens to your files.
Does the timer keep running if I switch tabs?
Yes, the timer continues running in the background as long as the browser tab stays open.
Can I track lap times with the stopwatch?
Yes, a lap button records each split time while the stopwatch keeps running.
Will I get a sound alert when the countdown finishes?
Yes, an audible alert plays when the countdown reaches zero, as long as your browser tab has permission to play sound.
Will it survive my phone locking?
Not reliably. Mobile browsers suspend background tabs aggressively to save battery, so a timer left running while the screen is off may not fire its alert on time. For anything you genuinely must not miss, such as food in the oven, use your phone’s own alarm app, which the operating system guarantees.
Why did no sound play?
Because browsers block audio until you have interacted with the page. Starting the timer normally counts as that interaction, but if the alert is silent, check the tab is not muted and that the site is permitted to play sound in your browser settings.
What happens if I refresh the page?
The timer resets. Nothing is stored between page loads, so a refresh or an accidental navigation loses the running count. Leaving the tab open is the only persistence there is.
How accurate is it?
Accurate to the timestamp rather than to counting ticks, so it stays correct even if the browser throttles the tab and the display updates less smoothly. Elapsed time is measured against the clock, not accumulated from intervals that might be skipped.
Start a stopwatch or countdown - free and instant.
Files never leave your device. No upload, no account, and free for unlimited use.
Also see: Pomodoro Timer, Countdown to Date