Online Timer

How do you set a timer for 5 minutes?

The page opens with 05:00 in the fields, so a 5 minute timer starts on a single click and a timer 5 minutes long needs no typing at all. Any other length goes into the three boxes above the ring: hours take 0 to 24, minutes take 0 to 1440 and seconds take 0 to 59.

Clicking one of the preset chips under the fields loads the duration and launches the count in the same gesture, which matters when the water is already boiling. Clicking a second chip mid-run restarts the count on the new duration, while the three boxes stay locked from Start until Reset, so a half-typed value never gets counted down.

Is there a 1 minute timer or a 10 minute timer?

Nine lengths sit under the fields at 1, 3, 5, 10, 15, 20, 30, 45 and 60 minutes, one click each. Every chip carries its length in the address, so a duration can be bookmarked, pinned to a task list or dropped into a message. The 5 minutes timer sits at /date/timer?minutes=5 and the twenty minute one at /date/timer?minutes=20. The same pattern holds for any value the minutes field accepts.

Does the timer keep running in a background tab?

It does, down to the second. The page notes the clock time at which the run should end, then reads the system clock four times a second to work out what is left, which is how a hidden tab ends up ringing at the same moment as a visible one.

Browsers throttle background tabs, that is they slow down the repeating scripts inside them, sometimes down to one run per minute. A countdown that adds up those ticks loses whole minutes over a long session, while this one recomputes the time left from the clock and catches up as soon as the tab comes back.

The tab title blinks between 00:00 and the page name every 0.9 seconds, the one part of the alert that carries to another tab along with the sound. The red panel and the pulsing ring wait on the timer's own tab.

Closing the tab is a different matter from hiding it. The run lives in the open page and nothing gets saved, so a reload, a closed tab or a restarted browser drops the count back to its starting duration. On a phone that includes a browser killed by the system behind another app.

What happens if the tab is muted or the device sleeps?

A muted tab, an unchecked sound box or a browser that blocks audio all land in the same place, with the red panel and the blinking title left to carry the alert. That silent mode is worth choosing on purpose in an open office or a library, where a 1046 Hz square wave is not welcome.

Sleep changes nothing either. A sleeping device suspends the page and no code runs at all, then on wake the timer compares its stored end time with the clock, finds it already passed and drops to 00:00 with the alarm on. A 20 minute timer started before a laptop lid closes will ring when the lid opens again.

How long can a single timer run?

A single run tops out at 24 hours, applied to the sum of the three fields whatever mix goes into them. Past the sixty minute mark the display switches from mm:ss to h:mm:ss, so a 90 minute session reads 1:29:59 a second after Start. The minutes box alone reaches 1440, which is what makes a link like ?minutes=90 valid without touching the hours field.

Anything above the ceiling gets clipped back to 24:00:00, so a stray 240 in the hours box costs nothing. Adding up several finished sessions is a different job, handled by the hours calculator.

What is the 25 minute Pomodoro timer?

A round is 25 minutes of work followed by a 5 minute break, with a longer pause of 15 to 30 minutes once four rounds are done. Francesco Cirillo described the technique in the late 1980s and named it after the tomato shaped kitchen timer he used as a student.

• Start a 25 minute run and work until the alarm.
• Switch to a 5 minute break, then start the next round.
• After four rounds, take 15 to 30 minutes away from the screen.

Those numbers are a scheduling convention, so people move them around freely.