3 hour timer
3:00:00
Press Start or the space bar.
3 hours at a glance
- On the timer
- 3:00:00
- Seconds
- 10,800
- Minutes
- 180
- Hours
- 3
- ISO 8601 duration
PT3H- Share of a day
- 12.5 %
- Back to back in 24 hours
- 8
When a 3 hour timer ends
The line under the timer shows the end time for your clock as soon as the page opens. For planning, here is where 3 hours lands from some common start times; late starts run past midnight:
| Start | Ends |
|---|---|
| 7:00 AM | 10:00 AM |
| 9:00 AM | 12:00 PM |
| 12:00 PM | 3:00 PM |
| 3:30 PM | 6:30 PM |
| 5:45 PM | 8:45 PM |
| 10:30 PM | 1:30 AM (next day) |
| 11:50 PM | 2:50 AM (next day) |
3 hours is longer than many computers’ and phones’ sleep settings. A sleeping device runs no web pages, so plug in and keep the screen on for this one. If the device does sleep, the timer is still right when it wakes, because it counts down to a fixed end time instead of counting ticks, and it rings at once if that time has passed.
A daylight saving change does not shorten or lengthen the timer: it measures 3 hours of real time. What changes is the clock reading at the end. On the night clocks go back an hour (2:00 AM daylight time becomes 1:00 AM standard time in the US), a 3 hour timer started at 1:30 AM ends when the clock shows 3:30 AM, not one hour later. If you need something to happen at a clock time, use an alarm instead.
For long work sessions, the Intervals mode can split 3 hours into blocks with breaks, for example work 50:00, rest 10:00, 3 rounds, and the label keeps the task name in the tab title.
Questions
How do I set a timer for 3 hours?
How many seconds is 3 hours?
PT3H.