Interval Timer
Set your work and rest lengths and the number of rounds, press start, and let the beeps run the workout. The timer keeps exact time in a background tab and counts you in for the last three seconds of every phase.
How to use the interval timer
- Enter work seconds, rest seconds and rounds, or tap a preset such as Tabata 20/10 × 8.
- Press Start. A short get-ready countdown runs before the first round.
- One high beep starts a work period, two lower beeps start a rest, and the last three seconds of every phase tick down.
- Pause, skip a phase or reset at any time. Your setup is remembered for next time.
How this timer works
What is an interval timer?
A timer that alternates fixed periods of work and rest for a set number of rounds and signals every switch, so you can train without watching a clock. It suits HIIT, circuits, sprints, rowing pieces and any drill built on repeats.
What is the difference between HIIT and Tabata?
Tabata is one specific HIIT protocol: 20 seconds of all-out effort, 10 seconds of rest, 8 rounds, four minutes in total. HIIT is the general category and can use any work-to-rest ratio and any number of rounds.
Does it keep going if I switch tabs or my screen locks?
The schedule is anchored to your device clock, so the timing stays exact however long the tab was in the background. Sound is the limit: beeps only play while the page is open in the browser, and a locked phone will usually silence them. For a workout you follow by ear, keep the page in the foreground.
Is there a rest after the last round?
No. The session ends when the final work period ends, so you never sit through a pointless last rest.
Is it free, and do I need an account?
It is free with no account and no install. Everything runs in your browser, and your last settings are remembered on this device.