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Workout timer

Interval
Timer

Plan HIIT, Tabata, or circuit work and rest intervals. Set work time, rest time, and rounds to plan your interval session.

Start Interval Timer Explore Workout Timers
100% privateInstant resultsNo sign-up
1Enter your details

Calculate your result

Use realistic, recent measurements for the most useful estimate.

100% privateInputs stay in this browserInstant resultsCalculated in real timeNo sign-upFree to use
2Your result
Interval TimerREADYStart with the form

Your result will appear here

Complete the form and select “Calculate result.” Your measurements never leave this page.

Educational estimate only—not medical advice.
Understand your result

How your Interval Timer estimate is created

A transparent overview of the inputs, method, and appropriate interpretation.

Evidence-informed Browser based
How it works

About this Interval Timer estimate

It combines work time, recovery time, and round count to show the planned session duration and repeatable interval structure.

Work-rest interval schedule
Work + rest + rounds→Interval schedule=Planned session
  1. 01Enter details
  2. 02Review inputs
  3. 03Use the estimate
Private by designNo account requiredInputs are not stored
Common questions

Interval Timer FAQ

Clear answers to help you understand and use your estimate.

01Is the Interval Timer free and private?

Yes. It is free, runs in your browser, requires no account, and does not store the measurements you enter.

02Can I use this result as medical advice?

No. This result is an educational estimate, not a diagnosis or treatment recommendation. A qualified professional can interpret it within your complete health and training context.

03Why might my Interval Timer result differ from a real-world result?

Transitions, pauses, warm-up, cool-down, fatigue, and exercise choice can make real session duration and effort differ from the plan.

04How often should I recalculate Interval Timer?

Update the plan whenever round count, exercise intensity, work duration, or recovery duration changes.

Read our calculation methodology →Still have questions? Explore the guides ↗