How do I set a five, ten or thirty minute countdown?

Choose 5 min, 10 min or 30 min and press Start. The 15 min and 20 min buttons work the same way. A quick button only changes the length; it does not start the timer or replace an active run.

Does changing Length interrupt a running or paused countdown?

The current countdown keeps its started length. At the next Start or Resume, the new valid length takes effect. If the old countdown has finished or the new length is already shorter than elapsed time, Restart begins from zero. Stop is available while Length is invalid.

Can I set an event date, repeat rounds or count several timers at once?

This page runs one duration countdown. Days Until counts to local midnight on a chosen date. Interval Timer runs work/rest rounds; Classroom Timer runs named activities in sequence. This countdown has no automatic loops or concurrent timers.

Does the countdown alarm work when the tab is hidden?

The page attempts three beeps when it observes the deadline and flashes the tab title. Hidden tabs, locked screens, muted audio and sleeping devices can delay or silence the sound. The overdue reading shows when the deadline was due on the browser clock; it does not prove a beep was heard. Closing the tab stops alarm delivery. A restored run has no automatic sound permission: Stop and Restart deliberately to try sound again.

What can I type in the countdown length box?

5:00 for five minutes, 90 for ninety seconds (a bare number is seconds), 1h 20m, or 00:00:30. Words work too: 45 sec, 25 minutes, 2 hours, 1.5h, 2m30s. A unit form can go over sixty, so 90s is a minute and a half. The seconds in a colon form cannot: 1:75 is refused, with the time you probably meant, 02:15, offered instead. Minutes can, as long as you are not also writing hours, so 90:00 is an hour and a half.

Countdown Timer

Choose a duration, then press Start. This page opens in Countdown with 5:00 selected, even if a different Stopwatch mode was saved. Quick buttons set 5, 10, 15, 20 or 30 minutes without starting a run; type a custom length for anything else. 90 means ninety seconds, 5:00 means five minutes, and 1h 20m means eighty minutes. Pause with Stop and continue with Resume; a completed or shortened countdown offers Restart. Editing Length keeps the active countdown at its original length until your next Start or Resume. At zero the deadline stays visible and the page attempts three beeps; browser audio permissions, hidden tabs and device sleep can delay or silence them. This is a duration timer. Use Days Until for a birthday, Christmas, New Year or retirement date at local midnight.

Countdown · ready05:00.0000:00 of 05:00 elapsed

Space start and stopR resetF full screen

Mode

Length

Show

Pick a length, then press Start.

The shortcuts work once you have clicked or tabbed into the tool, while the clock is on screen. Until then the space bar scrolls the page as usual.

When the deadline is observed, the tab title flashes and the page attempts three beeps. A hidden or sleeping device may delay or silence them. Keep this page open for an alarm.

Open Countdown Timer for a set duration. For repeated rounds use Interval Timer; for focus sessions use Pomodoro. Choose Classroom Timer for named activities and a progress bar, Chess Clock for two players, or Cube Practice Timer for scrambles and solve averages. For a birthday, retirement or holiday date, use Days Until (local midnight). For names or groups use Random Name Picker or Random Team Generator; use Dice Roller for random dice. This page has one digital timer; it has no animated races, themed clocks, voice activation or concurrent timers.

Common questions

How do I set a five, ten or thirty minute countdown?: Choose 5 min, 10 min or 30 min and press Start. The 15 min and 20 min buttons work the same way. A quick button only changes the length; it does not start the timer or replace an active run.
Does changing Length interrupt a running or paused countdown?: The current countdown keeps its started length. At the next Start or Resume, the new valid length takes effect. If the old countdown has finished or the new length is already shorter than elapsed time, Restart begins from zero. Stop is available while Length is invalid.
Can I set an event date, repeat rounds or count several timers at once?: This page runs one duration countdown. Days Until counts to local midnight on a chosen date. Interval Timer runs work/rest rounds; Classroom Timer runs named activities in sequence. This countdown has no automatic loops or concurrent timers.
Does the countdown alarm work when the tab is hidden?: The page attempts three beeps when it observes the deadline and flashes the tab title. Hidden tabs, locked screens, muted audio and sleeping devices can delay or silence the sound. The overdue reading shows when the deadline was due on the browser clock; it does not prove a beep was heard. Closing the tab stops alarm delivery. A restored run has no automatic sound permission: Stop and Restart deliberately to try sound again.
What can I type in the countdown length box?: 5:00 for five minutes, 90 for ninety seconds (a bare number is seconds), 1h 20m, or 00:00:30. Words work too: 45 sec, 25 minutes, 2 hours, 1.5h, 2m30s. A unit form can go over sixty, so 90s is a minute and a half. The seconds in a colon form cannot: 1:75 is refused, with the time you probably meant, 02:15, offered instead. Minutes can, as long as you are not also writing hours, so 90:00 is an hour and a half.

Time uses browser timestamps rather than counted ticks, so a background tab does not lose missed updates. Hundredths show display resolution, not certified accuracy. Device sleep may pause the browser clock; reloads use the device wall clock. A countdown reports how long ago its deadline passed; sound can be delayed or silent.