Interval timer

This interval timer alternates work and rest for up to 99 rounds. Set a schedule, check its total, and follow the phase cues with the page visible.

Why use intervals?

Intervals divide an activity into repeated periods. In a run/walk session, one period is running and the next is walking. In a workout, the recovery is part of the plan, giving you time before the next effort.

This structure makes the work and recovery explicit. It does not require every effort to be intense. Read how interval training works for the distinction between a timing pattern and HIIT, or how run/walk training uses intervals.

Choose work, rest and rounds

Work and Rest use whole minutes on this page. Rounds is the number of times the pair repeats. For example, Work 3, Rest 1 and Rounds 8 take 32 minutes. That includes one minute of recovery after the last work period.

The default is 30 minutes of work and 5 minutes of rest for eight rounds: 280 minutes altogether. Change those values to match your plan before starting. For durations such as 30 or 90 seconds, use an editable preset below.

One block or repeating reminders

Set Rest to 0 when you want consecutive work blocks without a break phase. Work 10 and Rounds 6 then give you one hour, with boundaries every ten minutes and a finish cue at the end. Set Rounds to 1 for one timed block.

For fixed starts with recovery inside each block, try EMOM. For a focus cycle with short breaks and a final long break, use Pomodoro. The work and recovery guide explains what changes when you adjust the ratio.

Before you press Start

Start begins the first work period immediately. Test your volume and get ready first. A rising tone marks work, a falling tone marks rest, and warning ticks occur in the final three seconds of a phase.

Keep the page visible when cues matter. The timer requests an awake screen, but the browser can refuse it. If the page is suspended, the countdown can catch up when it resumes; sound may arrive late or be missed. Pause holds your place, and End session asks before ending a running or paused session.

Ready-made timers

These pages open with a specific schedule and let you edit Work and Rest in seconds.

Common questions

Can I make it beep every 10 minutes for half an hour?

Yes. Set Work to 10 minutes, Rest to 0 and Rounds to 3. Any "beep every few minutes" timer works the same way, and the ready-made pages open with the numbers filled in.

Is the rest after the last round included?

Yes. Eight rounds of 3 minutes work and 1 minute rest last exactly 32 minutes. The session ends after the final rest, so the last sound you hear is the finish, not a work beep.

What are the limits?

On this page, Work runs from 1 to 60 minutes, Rest from 0 to 60 minutes and Rounds from 1 to 99. Preset pages set Work and Rest in seconds, up to 3,600. A number outside the range stays on screen with a note, so you can fix it yourself.

Will it beep if I switch to another app?

Not reliably. In a background tab, browsers slow timers down, so a beep can come late or not at all. The time stays right because it’s read from the clock, but keep the page on screen for beeps on time.