Online Timer

How this timer works

Type a number of hours, minutes and seconds into the three fields (or tap a quick-duration chip below the display to fill them in for you), then press Start. The big display counts down second by second. You can Pause and Resume at any point, or hit Reset to clear it and start over.

Unlike a countdown that simply subtracts one second from a running total every tick (which can slowly drift if a browser tab is backgrounded and its timers get throttled), this timer calculates a fixed end time the moment you press Start and always displays exactly how much real time is left until that moment. Switch to another tab, let your laptop go idle for a few minutes, then come back: the remaining time is still accurate.

Quick durations, one click

Nine common lengths sit as chips right under the display: 1, 5, 10, 15, 20, 25, 30, 45 and 60 minutes. Tap one and the hour/minute/second fields fill in automatically; press Start when you're ready. This is exactly what the 5 minute timer, 10 minute timer and 30 minute timer pages do automatically for their specific duration, if you'd rather land directly on a pre-filled countdown instead of setting it yourself.

• 1 minute, a short break, a single set of push-ups, boiling an egg-white-only omelette
• 5 or 10 minutes, a quick warm-up, a coffee break, brushing your teeth twice over
• 15 or 20 minutes, a focused work sprint, a short meeting slot, a HIIT circuit
• 25 minutes, the classic Pomodoro focus block (pair it with a 5-minute break)
• 30 or 45 minutes, a study session, a workout, a presentation slot
• 60 minutes, a full meeting, a class period, a long study block

Set any custom time

The three fields accept whole numbers: hours from 0-99, minutes and seconds from 0-59 each. That covers everything from a 10-second countdown to a 99-hour, 59-minute, 59-second one (just under four and a half days), useful for anything from a quick reaction-time drill to a multi-day event countdown. A few concrete examples:

Whatever the use case, type the exact hours/minutes/seconds you need, there's no requirement to pick a preset.

Alarm sound and fullscreen mode

When the countdown reaches zero, the timer plays a short, clear two-tone alarm (generated directly in your browser, no audio file to download, so the page stays light) and shows a large "Time's up!" message on screen. If you'd rather work in silence, tap the speaker icon to mute the alarm before you start, the visual "Time's up!" message still appears either way.

The fullscreen icon expands the timer to fill your entire screen, with no browser toolbar or address bar in the way, useful for a classroom projector, a shared meeting screen, or just making the numbers easier to read from across a room. On devices where the browser doesn't support true fullscreen for a single element (notably Safari on iPhone), the timer automatically falls back to a full-page view with the same result. Press Esc or tap the fullscreen icon again to exit.

Why use a web timer instead of your phone's clock app

Your phone almost certainly already has a timer built in. A few situations where a page like this one is still genuinely more convenient:

1. Sharing your screen on a video call or livestream: a browser tab is visible to everyone watching, unlike your phone's lock screen.
2. Projecting onto a classroom or meeting-room screen: fullscreen mode turns any laptop or desktop into a large, easy-to-read countdown display.
3. Working on a shared or locked-down computer, for example a school or library machine, where installing a timer app isn't possible but opening a web page always is.
4. Running the timer alongside other browser tabs and windows without picking up your phone, and without the distraction of notifications that come with unlocking it.

Accuracy, background tabs, and battery

Modern browsers deliberately slow down ("throttle") JavaScript timers in tabs that aren't currently visible, to save battery and CPU. A countdown built the naive way, subtract one second from a counter every time a timer fires, can quietly fall behind in a backgrounded tab, sometimes by many seconds over a long countdown. This timer avoids that: the moment you press Start, it calculates the exact clock time the countdown will finish, and every update simply compares the current time against that fixed target. However long the tab was throttled in between updates, the very next update snaps straight back to the correct remaining time, there's no accumulated drift to correct for.

Light or dark theme, and accessibility

Use the theme switch in the header to flip between a light and a dark color scheme; your choice is remembered in your browser for next time. All the buttons are large enough to tap comfortably on a touchscreen (at least 44x44 pixels, following standard accessibility guidance) and fully operable from a keyboard. The countdown display doesn't announce every second to screen readers, that would be unusable, but a screen reader is told, once, the moment the countdown finishes.

Using the timer for focused work (the Pomodoro technique)

One of the most common reasons people search for a countdown timer is a work technique named after the tomato-shaped kitchen timer it was originally built around: pick one task, work on it without interruption for a fixed block of time, then take a short break, and repeat. Tap the 25 minute chip for the classic focus block, work until the alarm sounds, then set a fresh countdown for a 5 minute break using the matching chip. After four rounds, most people take a longer break (15-30 minutes) before starting the cycle again.

The technique doesn't require any special software, a plain countdown timer with a clear alarm is really all it needs. Because everything here runs in a normal browser tab, you can keep it open in a small window off to the side of your screen, or expand it to fullscreen if you want the remaining time to be impossible to ignore.

Troubleshooting

A short list of the handful of things that occasionally trip people up:

• The alarm didn't play. Browsers block audio from playing automatically until you've interacted with the page, pressing Start counts as that interaction, so this is rarely an issue in practice. Check the mute icon isn't active, and check your device's own volume or silent/mute switch.
• The countdown fields won't accept a number bigger than expected. Hours are capped at 99 and minutes/seconds are capped at 59 each, matching how a clock reads, to set 90 minutes, either enter 1 hour 30 minutes, or set the minutes field to 90 (it will still work, the display simply carries it over correctly once the countdown starts).
• Fullscreen mode didn't fill the whole screen on my iPhone. iOS Safari doesn't support the standard Fullscreen API for a single page element, so the timer automatically switches to a full-page layout instead, visually the same result, just a different technique under the hood.
• I refreshed the page and my countdown was gone. By design, nothing is saved between page loads (see the privacy policy), a countdown in progress is tied to that specific browser tab. Avoid refreshing or closing the tab while a countdown you care about is running.

Frequently confused: timer vs. stopwatch vs. alarm clock

These three tools are easy to mix up but do genuinely different things. A timer (this page) counts DOWN from a duration you set to zero. A stopwatch counts UP from zero, typically to measure how long something takes (a run, a task, a race) rather than to enforce a limit. An alarm clock goes off at a specific clock time you choose (for example 7:00 AM), regardless of how much time is left between now and then. If you're looking for one of the other two, this page isn't the right tool, a countdown timer is specifically for "how much time is left until this duration runs out", not "how much time has passed" or "what time is it when this goes off".