Programmable Interval Timer

Updated 2026-05-17

Build any interval sequence you need. Add work and rest periods, name each one, set exact durations, choose how many rounds to repeat, and press start. Audio beeps count you down at each transition. Drag intervals to reorder them. No signup, no ads, no limits.

How to Use This Programmable Interval Timer

1. Add intervals. Click "+ Work interval" or "+ Rest interval" to add as many phases as you need. Each interval gets its own name and duration.
2. Set durations. Enter minutes and seconds for each interval. There are no preset limits. You can program 5 seconds or 50 minutes per interval.
3. Reorder by dragging. Grab any interval row and drag it to a new position in the sequence.
4. Choose rounds. Set how many times the full sequence repeats. One round plays through the list once. Three rounds plays it three times.
5. Set a countdown. The countdown gives you time to get ready before the first interval starts. Set it to 0 to start immediately.
6. Press Start. Audio beeps play at 3, 2, 1 seconds before each transition and a higher tone signals the switch. Pause and resume at any time.

What Makes a Timer "Programmable"

A programmable interval timer lets you define every detail of your interval sequence instead of choosing from preset templates. You control the number of intervals, the duration of each one, what each interval is called, and how many times the sequence repeats. This is the difference between a fixed Tabata timer (always 20 seconds on, 10 seconds off, 8 rounds) and a tool that lets you build any structure.

Use cases for a programmable interval timer include:

• HIIT workouts with varying work and rest ratios (30/30, 40/20, 45/15, or asymmetric patterns)
• Circuit training with named exercises and different durations per station
• Tabata variations beyond the standard 20/10 protocol
• EMOM workouts (every minute on the minute) with 60 second intervals
• Boxing rounds (3 minutes work, 1 minute rest, 12 rounds)
• Stretching routines with 30 to 60 seconds per position and short transitions
• Meditation and breathing sequences with timed inhale, hold, and exhale phases
• Study sessions using the Pomodoro technique (25 minutes focus, 5 minutes break)
• Physical therapy protocols with hold durations and rest periods prescribed by a therapist

Preset Templates

While this timer is fully programmable, here are common starting points you can build from:

Classic Tabata

8 rounds of 20 seconds work, 10 seconds rest. Total time: 4 minutes. The original protocol from Dr. Izumi Tabata's 1996 research on anaerobic capacity. Add two intervals (20s work, 10s rest) and set rounds to 8.

30/30 interval running

Equal work and rest. 30 seconds of hard running followed by 30 seconds of easy jogging. Set 10 to 15 rounds for a solid 10 to 15 minute interval block within a longer run. See our interval training for running guide for programming details.

Boxing rounds

3 minutes of work, 1 minute of rest. Professional boxing uses 12 rounds. Amateur uses 3 to 4. Program a single 3:00 work / 1:00 rest pair and set rounds accordingly.

EMOM (Every Minute on the Minute)

One work interval of 60 seconds, no rest interval. The "rest" is however much of the 60 seconds remains after completing the prescribed reps. Set rounds to 10, 15, or 20 depending on your workout length.

Pomodoro technique

25 minutes of focused work, 5 minutes of break. Set rounds to 4 for a standard 2 hour Pomodoro block. After 4 rounds, take a longer 15 to 30 minute break (run a second timer for this).

Tips for Effective Interval Training

1. Match your work/rest ratio to your goal. Short rest relative to work (2:1 or 3:1) builds anaerobic capacity. Equal or longer rest (1:1 or 1:2) lets you maintain higher intensity each work period, building power and speed.
2. Name your intervals clearly. When audio beeps fire during a workout, seeing "Burpees" or "Mountain Climbers" on screen (or hearing it via text-to-speech on a native app) removes the mental overhead of remembering what comes next.
3. Start conservative on rounds. It is better to finish 6 rounds feeling strong than to fail at round 4 of a planned 10. You can always add rounds next session.
4. Use the countdown. A 5 to 10 second countdown before the first interval lets you get into position and take a breath. Skipping it often means a wasted first interval.

Frequently Asked Questions

What is a programmable interval timer?

A programmable interval timer is a timer that lets you define custom sequences of timed intervals with different durations, names, and repeat counts. Unlike a simple stopwatch or a fixed-format timer, a programmable interval timer lets you build any pattern of work and rest periods for workouts, productivity, cooking, or any activity that benefits from structured time blocks.

Is this interval timer free?

Yes. This is a free programmable interval timer with no signup, no ads, and no usage limits. It runs entirely in your browser. Your intervals are not saved to a server (refresh the page to start fresh, or bookmark this page to come back).

Does it work on my phone?

Yes. This timer is fully responsive and works on any modern browser, including Safari on iPhone, Chrome on Android, and all desktop browsers. For the best experience during workouts, keep the browser tab in the foreground so audio beeps are not interrupted by the operating system.

Can I save my timer programs?

This web version does not save programs between sessions. For saved programs, shareable timers, and Apple Watch support, try the PEAKVO2 app. A future update to this page will add local storage for saving your favorite timer configurations.

What is the difference between work and rest intervals?

They are functionally identical (both count down for the duration you set). The distinction is visual and organizational: work intervals display in green, rest intervals display in amber. This helps you scan your timer structure at a glance and provides clear visual feedback during the workout about whether you should be pushing hard or recovering.

How many intervals and rounds can I add?

There is no limit. Add as many intervals as your workout requires, and set up to 100 rounds. The timeline bar at the top gives you a visual overview of your full session regardless of length.