HIIT Timer

Run a HIIT session with the work interval, rest interval and number of rounds you choose.

How to use HIIT Timer

1. Enter Work Interval, Rest Interval, Rounds. 2. Plain numbers mean minutes; labelled d, h, min and sec are accepted. Durations are non-negative and a duration day means 24 hours. Static answers round to seconds, with nonzero subsecond values labelled. No holiday calendar or daylight-saving adjustment is applied. Active phases must be at least one millisecond. Generated schedules support at most 10,000 phases to bound browser work; rest/transition occurs between active phases, not after the final one. The browser runs the timer while the page remains open. Background throttling, sleeping devices and blocked sound can delay visible updates or alerts. Use Pause/Resume where shown and Reset to stop/clear it; this is not a guaranteed alarm or safety clock. 3. Select Start to start the displayed timer. Use its Pause/Resume controls where shown; Reset stops and clears it.

Why use this tool?

Use HIIT Timer when you need hiit session duration. Plain numbers mean minutes; labelled d, h, min and sec are accepted. Durations are non-negative and a duration day means 24 hours. Static answers round to seconds, with nonzero subsecond values labelled. No holiday calendar or daylight-saving adjustment is applied. Active phases must be at least one millisecond. Generated schedules support at most 10,000 phases to bound browser work; rest/transition occurs between active phases, not after the final one. The browser runs the timer while the page remains open. Background throttling, sleeping devices and blocked sound can delay visible updates or alerts. Use Pause/Resume where shown and Reset to stop/clear it; this is not a guaranteed alarm or safety clock.

How the calculation works

Whole rounds of positive work with optional non-negative between-round rest. Plain numbers mean minutes; labelled d, h, min and sec are accepted. Durations are non-negative and a duration day means 24 hours. Static answers round to seconds, with nonzero subsecond values labelled. No holiday calendar or daylight-saving adjustment is applied. Active phases must be at least one millisecond. Generated schedules support at most 10,000 phases to bound browser work; rest/transition occurs between active phases, not after the final one. The browser runs the timer while the page remains open. Background throttling, sleeping devices and blocked sound can delay visible updates or alerts. Use Pause/Resume where shown and Reset to stop/clear it; this is not a guaranteed alarm or safety clock. Live timer values show the current elapsed/remaining clock; the worked example describes the starting schedule.

Example

Worked example: Work Interval = "1 min"; Rest Interval = "30 sec"; Rounds = 2. Result: Work 1/2 starts at 01:00; Rest 1/2 is 00:30; Work 2/2 is 01:00.

Practical tip

Check the hiit input and output convention before reusing the result.