Interval Workout Timer
Run HIIT, Tabata, circuit, or EMOM sessions hands-free. The timer auto-cycles work, rest, rounds, and sets — with countdown beeps in the final seconds and a Wake Lock so your screen stays on.
How to Use
Tabata (20s/10s × 8R), HIIT (45s/15s × 10R), EMOM (60s × 10R) — or set work / rest / rounds / sets / set-rest manually.
5-second prep → work → rest → next round, automatic. Big on-screen progress like '3/8 rounds, 1/2 sets'.
Last 3 seconds of each phase get a beep-beep-beep countdown; phase transitions use distinct tones. Works through wireless earbuds.
FAQ
What's the difference between Tabata and HIIT?
Tabata is a specific 4-minute protocol developed by Dr. Tabata: 20s all-out + 10s rest × 8 rounds. HIIT is the broader term — any high-intensity interval training with custom work/rest ratios.
My screen keeps turning off
With 'Keep screen on' enabled, the Wake Lock API prevents the screen from sleeping during a session. Some older mobile browsers don't support it.
No sound on iPhone
iOS Safari mutes site audio when the device is in silent mode. Switch off silent mode and raise the volume. The first 'Start' tap activates audio — keep the screen visible for the first run.
Does it run in background tabs?
Browsers throttle JS timers in background tabs, which can drift the timing. For accurate sessions, keep the tab visible — the screen-on option helps.
Is anything sent to a server?
No. All timer logic runs in your browser; settings are stored in localStorage only.
