How do I set a 5 minute timer?
Tap 5 min, then Start. The ring empties as the time runs down, the page title shows the time left so you can see it from another tab, and a chime plays at zero. Stop pauses it; Start carries on from where it stopped.
Countdown Timer
Tap 5 min and Start, or count down the days to a date. It keeps time from the moment it ends.
Your countdown
Your countdown
Set a timer or a date above.
The working
Time left = end time − now, shown in minutes and seconds
Pressing Start records the moment the timer will end: now + 5:00. Every tenth of a second the page subtracts the clock from that moment and rounds up to the whole second. For a date: Friday, 25 December 2026 at 00:00 − now = 4,536,000 seconds = 52 × 86,400 + 12 × 3,600 + 0 × 60 + 0.
Worked examples
- A 25-minute focus block started at 9:50 ends at 10:15.
- Tabata, 8 rounds of 20 s on and 10 s off: 3:50 in all.
- A boiled egg: 6 minutes for a soft yolk, 9 for hard, from when the water returns to the boil.
- From noon on 1 December to midnight starting 25 December is 23 days and 12 hours, but 24 sleeps.
Good to know
Timers that never drift
- Count to an end time, not by ticks. Browsers slow down timers in background tabs; a timer that adds up ticks falls behind, one that checks the clock does not.
- Sleeps are not days. From Monday evening to Wednesday morning is under two days but two sleeps. Children count sleeps; the chart below counts them for you.
- Sound needs a tap first. Browsers only allow sound after you press something on the page, which Start does.
- Time zones: a countdown to an event elsewhere, such as a New Year’s Eve broadcast, should use the event’s time as it will be where you are.
Questions
Questions people ask about countdown timers
Will the timer keep going if I switch tabs or lock my phone?
It keeps counting, because it works from the moment it will end, not by counting ticks, so it is right again the moment you come back. Browsers can silence or delay sound in background tabs, and a locked phone may not play the chime at all, so for anything that matters, such as medicine or cooking, keep the page open on screen.
How many days until Christmas?
Use the Until a date tab: it opens on the next 25 December. From noon on 28 October 2026 (UTC) it is 57 days and 12 hours to midnight on Christmas morning. Children often count sleeps instead: the number of nights, which is the number of calendar days to the date.
What is a Tabata timer?
Eight rounds of 20 seconds’ hard work and 10 seconds’ rest. Without a rest after the last round that is 3:50 in all. Set it in the Intervals tab: 8 rounds, 20 s work, 10 s rest.
Does the countdown to a date allow for daylight saving?
Yes. It counts real elapsed time to the event in your own time zone, so a countdown across a clock change is an hour longer or shorter than the calendar suggests. For an event in another time zone, set the time as it will be where you are.
Why does the timer show 0:01 for the last second?
Because it rounds up: 0:01 means part of a second is left. A timer that rounded down would show 0:00 while there was still time to go, and finish a second after it said it had.
Print room
A cross-off countdown chart
One square for every sleep until Christmas (up to 100), to colour in or cross off each night: for a holiday, a birthday, Christmas or an exam. Set the date in the Until a date tab first.
For code
The same countdown in code
import time
seconds = 300
end = time.monotonic() + seconds
while (left := end - time.monotonic()) > 0:
print(f"\r{int(left // 60)}:{int(left % 60):02d}", end="")
time.sleep(0.2)
print("\nTime's up")Both count to an end time, so they keep good time.
53 sleeps until Christmas!
Friday, 25 December 2026 at 00:00 · Cross off one square each night.
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calculationtime.com/calculators/countdown-timer/
Sources