Workout Interval Timer
HIIT and circuit training timer with custom rounds, work/rest intervals, audio cues, and localStorage workout plans.
About this tool
Build custom HIIT, Tabata, EMOM, or circuit training workouts and run them with a full-screen interval timer. Create a workout plan by adding exercises, each with its own work duration, rest duration, and number of rounds. The large animated SVG countdown circle shows the remaining time at a glance, and the current exercise name and round count are displayed prominently beneath it. Three distinct audio tones are generated using the Web Audio API: a double beep at the start of each work interval, a single beep at the start of each rest interval, and a triple chime when the entire workout is complete — no audio files required. Three built-in presets get you started instantly: Tabata (8 rounds × 20s work / 10s rest), EMOM (every minute on the minute for 10 rounds), and an AMRAP countdown timer. Save and load your custom workout plans from localStorage so your routines are always ready.
How to use
- 1 Select a preset (Tabata, EMOM, or AMRAP) or build a custom workout by clicking 'Add Exercise'.
- 2 For each exercise, enter the name, work time (seconds), rest time (seconds), and number of rounds.
- 3 Click 'Save Plan' to store the workout in localStorage for future sessions.
- 4 Click 'Start' — the large countdown circle begins and audio cues guide each interval.
- 5 Use the Pause and Reset buttons to control playback at any time.
Frequently Asked Questions
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