Interval timer: a simple clock for movement and rest
Set a movement interval, a rest interval and a round count. Start, pause, resume or stop the silent clock whenever you need.
Interval Timer
A simple clock for movement and rest. Set your work and rest windows, choose a preset or dial in your own, and let the ring, colour and sound cues keep you on pace — no external app required.
Tap play to start — sound cues fire on each phase change.
Interval training alternates short bouts of higher-intensity work with recovery periods. The work-to-rest ratio determines which energy system you lean on. A 1:1 ratio (like 40 seconds on, 40 off) sits at a sustainable threshold intensity. A 2:1 ratio (like the classic Tabata protocol of 20 seconds all-out and 10 seconds rest, repeated eight times) drives the anaerobic system hard and is best reserved for one or two sessions per week, as the original Tabata study found. A 1:3 or 1:4 ratio — 30 seconds hard, 90 seconds easy — keeps work quality high and is more forgiving for repeat sessions. The ACSM classifies interval work as vigorous-intensity activity and counts it toward the 75 minutes per week recommended for adults. Audio cues help because they free you from watching the clock — three short beeps mark the start of work, two mark the start of rest, and one long beep signals completion. If you feel dizzy, breathless beyond recovery, or experience chest discomfort, stop. This timer is a reference tool — listen to your body first.
Prepare before you start
Choose five to 600 seconds for each movement and rest interval, then one to 30 rounds. Preparing the timer shows the settings without starting a countdown. Select Start when you are ready. There is no automatic audio, and the timer does not dictate how hard you should move.
How the timing works
Each round contains movement time. Rest separates rounds; there is no extra rest after the final movement interval. Five rounds of 30 seconds movement with 30 seconds rest therefore total 270 seconds, or 4 minutes 30 seconds. Pause preserves the remaining time; Resume continues from that point. Stop ends the prepared timer.
A clock is not an exercise prescription
Choose activity, duration and intensity appropriate to your circumstances. A countdown is not a reason to continue through pain or concerning symptoms. The timer can also organize easy movement breaks. It cannot monitor your body or identify an unsafe effort.
Keep the page visible
Browsers can throttle background tabs or suspend a device. The clock uses elapsed time to catch up after a delayed update, but it is not a safety-critical timing device. Keep the page visible and use another reliable clock when exact audible prompts are essential. Reloading the page clears timer state.
Sources and related tools
WHO physical activity guidance provides public-health context. It does not validate an individual exercise plan. Use the mobility routine for a short optional movement sequence, or create a week with the workout planner.
Editorial information
Prepared with AI assistance for Everyday Wellness Planner. Last checked: 9 October 2026. No independent clinical review is claimed. Read our editorial policy and educational disclaimer. Calculator inputs remain in this browser tab; ordinary site logs and analytics are described in the privacy notice.
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