Interval Timer
Free interval timer for HIIT, Tabata and circuit training. Configure prepare, work, rest and between-set phases with beep cues and an optional voice countdown. Total time estimate and one-tap presets.
How do I set up a Tabata workout?
Tap the Tabata preset, or manually set prepare to 10 s, work to 20 s, rest to 10 s, sets to 8 and cycles to 1. The total duration updates live as you edit.
What is the difference between sets and cycles?
A cycle is one complete group of work/rest pairs. Sets counts how many work-rest pairs make up each cycle, and between-set rest is inserted after every full cycle before the next one starts.
How does the voice countdown work?
Enable the 3·2·1 voice option and your browser’s built-in speech engine counts down the last three seconds of each work phase. No files are downloaded; it uses the local speech synthesis.
What do the different beeps mean?
A long tone announces the start of each work phase, a lower tone marks the switch to rest, and three short high beeps count down the final seconds of work so you know when to push.
Can I skip a phase or pause mid-workout?
Yes. Pause freezes the countdown and Resume continues it, while Skip jumps straight to the next phase. Reset returns everything to the beginning with your current settings.
Does the timer keep running if I switch tabs?
Yes, the countdown is based on real time, so switching tabs does not break it. Come back and the display catches up instantly; keep the tab open for the sounds to keep playing.
Can I use it for boxing rounds or studying?
Absolutely. Any work/rest pattern works: set the phases to 3-minute rounds with 1-minute rests, or use longer work phases as pomodoro-style study blocks.
Is anything uploaded to a server?
No. The timer, the beeps and the voice countdown all run locally in your browser. No settings or workout data leave your device.
How to Use Interval Timer
This interval timer builds HIIT, Tabata and circuit sessions from four phases — prepare, work, rest and between-set rest. It beeps at different pitches for each phase, can count down the last three seconds in your own language, and estimates the total workout duration as you edit. Everything runs locally in your browser.
- Pick a preset — Tabata 20/10×8, HIIT 40/20×10 or Circuit 45/15×6×3 — or type your own seconds into prepare, work, rest, sets, cycles and between.
- Check the total line under the fields to see how long the whole session will run.
- Press Start: the screen shows the current phase in its color, the next phase, your set and cycle position and the time left overall.
- Enable 3·2·1 voice to have the final seconds of each work phase spoken, and keep Beeps on for the phase-change tones.
- Use Pause to freeze, Skip to jump to the next phase, and Reset to return to the start with your current settings.
For strength circuits set 45-second work and 15-second rest phases with 3 cycles of 6 exercises — the between-set rest of 60 seconds gives you a full minute to set up the next round of equipment.
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