Countdown Timer
Online timer with alarm, presets, full screen and date countdowns.
A Timer That Rings, Even in a Background Tab
Tap a preset — 1, 3, 5, 10, 15, 20, 30, 45 minutes or an hour — or type any time up to 99 hours, and press Start. A progress ring shows how much is left, Pause and +1 minute are one tap away, and Full screen turns the countdown into a display big enough for a classroom, a gym or a meeting room.
The alarm is booked on your device’s audio clock the moment you start, so it still rings if you switch to another tab, and the time is kept from the end moment rather than by counting ticks, so it never drifts and even survives a page reload. Switch to Countdown to a date for days, hours and minutes until a birthday, a launch, an exam or New Year.
Key features
- One-tap presets and a custom hours-minutes-seconds timer.
- Reliable alarm with three sounds, vibration and optional notifications.
- Full-screen mode for classrooms and presentations.
- Countdown to any date with a label.
- No drift, survives reloads — timed from the end moment.
This tool runs entirely inside your browser using native Web APIs. Your files and text are never uploaded to a server, never logged and never shared with third parties.
How to use: Countdown Timer
- Choose the time
Tap a preset or type hours, minutes and seconds. - Pick an alarm sound
Beep, chime, digital or silent; tick Notify for a desktop notification. - Start
Press Start. Pause, add a minute or reset at any time. - Go full screen
Press the screen button to show the countdown large on any display.
Technical specifications
| Processing location | Entirely in your browser — no server round trip |
|---|---|
| Data uploaded | None. Files and text never leave your device |
| Price | Free — no account, no trial, no usage cap |
| Category | Calculators |
| Works offline | Yes, once the page has loaded |
| Browser support | Chrome 90+, Edge 90+, Firefox 90+, Safari 15+ |
| Interface languages | English, 中文, हिन्दी, Español, العربية |
Frequently asked questions
Will the alarm sound if I switch tabs?
Yes. The alarm is scheduled on the audio clock when you press Start, which keeps running in background tabs. Keep your volume up and the tab open.
What happens if I reload the page?
The timer is saved with its end time, so after a reload it carries on counting from where it should be.
Can I count down to a date?
Yes — choose Countdown to a date, give the event a name and pick the date and time. It shows days, hours, minutes and seconds remaining.
Is it accurate?
It is accurate to the second: the remaining time is calculated from the finish moment on every update, so a slow or busy device cannot make it run late.
Does it work on phones?
Yes. On phones the screen may sleep; keep it awake for long timers, or rely on the alarm sounding when the browser is still open.