Does the timer keep counting if I switch tabs or lock my phone?

Elapsed time is calculated from your system clock rather than accumulated from delivered ticks. When the browser resumes updates, the display catches up to that elapsed time. Beeps can be delayed or missed while a tab is throttled or a device sleeps. Closing the tab ends the session; changing the system clock can affect the reading.

Why does a tabata set come to 4:00 and not 3:50?

The final rest is included. Eight work intervals of 20 seconds plus eight rests of 10 seconds equal 240 seconds, or 4:00. Without the last rest the sequence would be 3:50. The strip includes that final rest before you start.

What does the Tabata pattern button set, and can I change the timings afterwards?

It sets 20 seconds of work, 10 seconds of rest and 8 rounds, with no warm up and no cool down, which comes to 4:00. Tabata is the name of a timing pattern and that is all this page means by it: the timer states intervals and rounds and never tells you what to do inside one. Every number stays an ordinary editable field after the pattern lands, so you can make it 30 and 15, or add a minute of warm up, and the sequence and the total are worked out again as you type.

Can I have a warm up, a cool down, or rounds with no rest at all?

Yes to all three. A warm up or a cool down of 0 leaves that interval out of the sequence entirely rather than showing an empty step, and a rest of 0 gives you back to back work intervals, which is how a one minute rounds session is set up. The work interval is the one value that cannot be 0, because a round has to have something in it. Timings are typed in seconds, or as minutes and seconds like 1:30, and a value that cannot be read is refused with a message naming the field rather than quietly turned into something near it.

Do I need an account or an app, and is the sound optional?

No account, no install, and nothing about your session leaves the page. The cue is a short tone the page synthesises with Web Audio rather than a file it downloads, so it also works with no network, and the Cue button turns it off. One browser rule applies to every site: there has to be a click on the page before any sound can play, which is what pressing Start provides.

Are my timings remembered, and how do I move around the sequence?

The five timings and the cue switch are kept in this browser only, and the Start over button at the top of the page forgets them. Skip moves to the start of the next interval, Restart goes back to the beginning of the first one, and any interval in the strip can be jumped to by clicking or tabbing to it. Moving about changes the elapsed time rather than a counter, so the reading stays exact wherever you land. Copy plan puts the whole sequence on the clipboard as text, one line per interval with the time it starts and the time it ends.

How do I set 30/30, 40/20 or 45/15 workout intervals?

Enter the first number in Work and the second in Rest, both in seconds, then set Rounds. For example, 40 seconds plus 20 seconds makes one minute per round, including the last rest. Warm up and Cool down add time at the ends. These are timing settings, without instructions for activity, effort or progression.

Can I time a single minute, seven minutes or thirty minutes?

Yes. Set Warm up, Rest and Cool down to 0, set Rounds to 1, and enter Work as 60, 420 or 1800 seconds respectively. One minute rounds is also a built-in pattern: ten 60-second work intervals with no rest, totaling 10:00.

Can I use it for circuit, HIIT or EMOM timing?

The timer repeats the same work and rest pair for each round. The built-in 45 on, 15 off pattern includes a warm up and cool down; One minute rounds supplies repeated minute boundaries. You provide the activities yourself. It does not count repetitions, recommend a workout, or build ladders with different interval lengths.

Does this workout timer include music or spoken countdowns?

It has optional synthesized beeps, with rising cues into work and falling cues into rest. It does not play music, songs or spoken instructions. Audio playback and timely cues depend on browser permission and whether the tab remains active.

Does this work on iPhone, Android, PC or Mac?

Use this page in a current browser on a phone, tablet or computer. Press Start to permit audio playback. The page does not supply an Apple Watch or Fitbit app; cues may be delayed or missed when a device sleeps.

Interval Timer

Set Work, Rest and Rounds to time repeated intervals for a workout or another timed task. Optional warm up and cool down sit at the ends. The complete sequence and session total are visible before you start, including the last rest. Timings can be seconds or minutes:seconds, and the Tabata pattern button sets an editable 20/10 sequence.

Warm up00:100:10 warm up, 8 rounds of 30 s work and 15 s rest. Total 6:10, the last rest counted.

Warm up: s
Work: s
Rest: s
Rounds
Cool down: s
Total: 6:10

Ready. Press Start to begin the first interval.

Tabata pattern20 on, 10 off, 8 rounds
4:00
45 on, 15 off8 rounds, 1 min warm up and 2 min cool down
11:00
One minute rounds60 on, no rest, 10 rounds
10:00

A round is one work interval followed by one rest interval, and the last rest is counted like every other one, which is why eight rounds of 20 and 10 come to 4:00 rather than 3:50. Type seconds, or minutes and seconds as 1:30. Skip moves to the next interval and any interval in the strip can be jumped to. Tabata is the name of a timing pattern, 20 seconds on and 10 off for eight rounds, and that is all this page means by it.

Exact about elapsed time. Exact to the timestamps your browser reports, so it does not drift while the tab is in the background. It is a timer and nothing else: the tabata pattern is a named timing pattern, not an exercise prescription.

Common questions

Does the timer keep counting if I switch tabs or lock my phone?: Elapsed time is calculated from your system clock rather than accumulated from delivered ticks. When the browser resumes updates, the display catches up to that elapsed time. Beeps can be delayed or missed while a tab is throttled or a device sleeps. Closing the tab ends the session; changing the system clock can affect the reading.
Why does a tabata set come to 4:00 and not 3:50?: The final rest is included. Eight work intervals of 20 seconds plus eight rests of 10 seconds equal 240 seconds, or 4:00. Without the last rest the sequence would be 3:50. The strip includes that final rest before you start.
What does the Tabata pattern button set, and can I change the timings afterwards?: It sets 20 seconds of work, 10 seconds of rest and 8 rounds, with no warm up and no cool down, which comes to 4:00. Tabata is the name of a timing pattern and that is all this page means by it: the timer states intervals and rounds and never tells you what to do inside one. Every number stays an ordinary editable field after the pattern lands, so you can make it 30 and 15, or add a minute of warm up, and the sequence and the total are worked out again as you type.
Can I have a warm up, a cool down, or rounds with no rest at all?: Yes to all three. A warm up or a cool down of 0 leaves that interval out of the sequence entirely rather than showing an empty step, and a rest of 0 gives you back to back work intervals, which is how a one minute rounds session is set up. The work interval is the one value that cannot be 0, because a round has to have something in it. Timings are typed in seconds, or as minutes and seconds like 1:30, and a value that cannot be read is refused with a message naming the field rather than quietly turned into something near it.
Do I need an account or an app, and is the sound optional?: No account, no install, and nothing about your session leaves the page. The cue is a short tone the page synthesises with Web Audio rather than a file it downloads, so it also works with no network, and the Cue button turns it off. One browser rule applies to every site: there has to be a click on the page before any sound can play, which is what pressing Start provides.
Are my timings remembered, and how do I move around the sequence?: The five timings and the cue switch are kept in this browser only, and the Start over button at the top of the page forgets them. Skip moves to the start of the next interval, Restart goes back to the beginning of the first one, and any interval in the strip can be jumped to by clicking or tabbing to it. Moving about changes the elapsed time rather than a counter, so the reading stays exact wherever you land. Copy plan puts the whole sequence on the clipboard as text, one line per interval with the time it starts and the time it ends.
How do I set 30/30, 40/20 or 45/15 workout intervals?: Enter the first number in Work and the second in Rest, both in seconds, then set Rounds. For example, 40 seconds plus 20 seconds makes one minute per round, including the last rest. Warm up and Cool down add time at the ends. These are timing settings, without instructions for activity, effort or progression.
Can I time a single minute, seven minutes or thirty minutes?: Yes. Set Warm up, Rest and Cool down to 0, set Rounds to 1, and enter Work as 60, 420 or 1800 seconds respectively. One minute rounds is also a built-in pattern: ten 60-second work intervals with no rest, totaling 10:00.
Can I use it for circuit, HIIT or EMOM timing?: The timer repeats the same work and rest pair for each round. The built-in 45 on, 15 off pattern includes a warm up and cool down; One minute rounds supplies repeated minute boundaries. You provide the activities yourself. It does not count repetitions, recommend a workout, or build ladders with different interval lengths.
Does this workout timer include music or spoken countdowns?: It has optional synthesized beeps, with rising cues into work and falling cues into rest. It does not play music, songs or spoken instructions. Audio playback and timely cues depend on browser permission and whether the tab remains active.
Does this work on iPhone, Android, PC or Mac?: Use this page in a current browser on a phone, tablet or computer. Press Start to permit audio playback. The page does not supply an Apple Watch or Fitbit app; cues may be delayed or missed when a device sleeps.

Exact to the timestamps your browser reports, so it does not drift while the tab is in the background. It is a timer and nothing else: the tabata pattern is a named timing pattern, not an exercise prescription.