Interval timer

What it does

Set work, rest and warm-up periods, with rounds, sound cues and a reusable local preset.

How to use it

1. Choose a preset or set work/rest durations, rounds and warm-up. Start, pause, resume or reset the session.
2. There is no rest after the last round. Save one preset on this device using browser storage; no account is required.
3. Keep the tab visible for timely sound cues. Background tabs and screen locks may delay updates; the display catches up using elapsed time.

Example

Eight 20-second work rounds with seven 10-second rests and a 10-second warm-up total four minutes.

Methodology

A monotonic browser clock measures elapsed time. Phase boundaries determine the display and optional Web Audio cues, with paused time excluded.

Limitations

Work 1–3,600 seconds, rest 0–3,600 seconds, warm-up 0–600 seconds and 1–100 rounds. Browser suspension can delay cues. Storage and sound may be unavailable.

Automation

This tool runs in your browser. No upload API or MCP endpoint is available.