How do I use this rest timer for strength training?

Enter your work time (for example 40 seconds), rest time (for example 90 seconds), and number of sets (for example 4). Optionally add a warm-up and cooldown. Click Start or press Space. The timer will automatically alternate between work and rest until all sets are completed.

Can I use this rest timer for HIIT or Tabata workouts?

Yes. For classic Tabata you can set 20 seconds work, 10 seconds rest, and 8 sets. For other HIIT protocols, just adjust the work, rest, and set count to match your plan.

Will the rest timer keep running if I switch tabs?

Yes. The timer is based on real time, not animation frames, so it keeps accurate time even if you switch tabs or the browser window is in the background. Make sure your device is not in sleep mode and that sound is allowed if you rely on audio alerts.

What keyboard shortcuts are available?

Space starts or pauses the timer, R resets the current session, and N skips to the next interval (for example from work to rest). These shortcuts work while the page is focused.

Can I mute or change the alert sounds?

Yes. You can choose between different alert sounds for work and rest, or mute them completely. You can also enable a 3-second countdown beep before each interval starts.

Rest Timer – Smart Interval & Workout Break Timer

How to use the rest timer

This rest timer is designed for strength training, bodybuilding, HIIT, Tabata, and circuit workouts. It alternates automatically between work and rest intervals, with optional warm-up and cooldown phases.

1. Configure your intervals

Work – the time you spend lifting, sprinting, or holding an exercise.
Rest – the break between sets or rounds.
Sets – how many work+rest cycles you want to complete.
Warm-up – optional time at the beginning (for mobility, light cardio, etc.).
Cooldown – optional time at the end (for stretching or breathing work).

As you change these values, the tool automatically updates the total session time so you know exactly how long your workout will take.

2. Start, pause, skip, and reset

Click Start or press Space to begin.
Click again or press Space to pause.
Use Skip Interval or press N to jump to the next phase (for example from work to rest).
Use Reset or press R to restart the whole session.

The circular ring and color indicate the current phase:

Green – work interval.
Blue – rest interval.
Purple – session finished.

3. Sounds and countdown

You can choose different alert sounds for work and rest, or mute them completely. The optional 3-second countdown plays short beeps before each interval starts, giving you time to get into position.

How total workout time is calculated

The timer builds a sequence of phases in this order:

Warm-up (if > 0 seconds)
Set 1: Work → Rest
Set 2: Work → Rest
… up to the number of sets you selected
Cooldown (if > 0 seconds)

Total time formula

Let:

W = work duration in seconds
R = rest duration in seconds
S = number of sets
WU = warm-up duration in seconds
CD = cooldown duration in seconds

Then the total session time is:

Total = WU + S × (W + R) + CD

The summary panel shows elapsed and remaining time based on this formula, updated in real time as the timer runs.

Example setups

Classic strength training

Work: 40 seconds (time under tension for a set)
Rest: 90 seconds
Sets: 4–6
Warm-up: 5 minutes (optional)
Cooldown: 5 minutes (optional)

Tabata protocol

Work: 20 seconds
Rest: 10 seconds
Sets: 8
Warm-up: 3–5 minutes
Cooldown: 3–5 minutes

Click the “Load Tabata preset” link to fill these values automatically.

Tips for effective rest timing

Strength & power: longer rests (2–5 minutes) help you maintain performance across heavy sets.
Hypertrophy: moderate rests (60–120 seconds) balance fatigue and volume.
Endurance & conditioning: shorter rests (20–60 seconds) keep your heart rate elevated.
Keep your phone or screen visible or rely on sounds so you don’t have to watch the clock constantly.

FAQ

Does the timer work offline?

Once the page is loaded, the timer logic runs in your browser. However, if you refresh the page while offline, it may not reload correctly.

Can I use this rest timer on mobile?

Yes. The layout is responsive and works on phones and tablets. For best results, keep the screen awake and volume on so you can hear the alerts.

Is this rest timer free?

Yes, this tool is completely free to use and does not require registration or downloads.