How to use the interval timer
Set how long each work interval lasts, how long you rest between intervals, and how many rounds you want, then press Start. You get a get-ready countdown first, a beep at every change between work and rest, and three short beeps before each change so you are never caught off guard.
Your settings are saved in the page address. Bookmark the page after setting it up and the same workout opens next time.
Common interval setups
- 40 / 20 — 40 seconds work, 20 seconds rest. A common circuit-training format.
- 30 / 30 — equal work and rest, easier to sustain for longer sessions.
- 45 / 15 — short rest for conditioning blocks.
- Running intervals — for example 60 seconds fast, 90 seconds easy, 8 rounds.
FAQ
Does the screen stay on? On browsers that support it, the timer asks your phone to keep the screen awake while it runs. If your browser does not support it, the timer still works, but your phone may lock.
Does it work in the background? The countdown is based on the real clock, so it stays accurate if you switch apps. Some phones mute sounds from background tabs, so keep the page open for beeps.
Popular presets
- 3 Round Boxing Timer — 3 x 3:00, 1:00 rest
- 30 / 10 Interval Timer — 30s on, 10s off
- 30 / 30 Interval Timer — 30s on, 30s off
- 30 / 15 Interval Timer — 30s on, 15s off
- 45 / 15 HIIT Timer — 45s on, 15s off
- 1 Minute Interval Timer — 60s on, 10s off