Interval Timer
Create custom interval workouts with our free online interval timer. Set work, rest, rounds and prepare times, then start your workout instantly.
Set Your Intervals
Set your prepare, work and rest times, choose your rounds and start your interval workout instantly.
What Is an Interval Timer?
An interval timer is a workout timer that alternates automatically between work and rest intervals. Instead of watching a stopwatch, you set your work time, your rest time and the number of rounds — the timer counts everything down for you, with audio cues at every transition.
An online interval timer is one of the most versatile training tools you can use. It works for HIIT, circuit training, bodyweight sessions, home workouts, running intervals and any workout built around work and rest intervals. Because it runs directly in your browser, there is nothing to download: open the page, set your intervals and start training. Whether you follow a structured program or build your own sessions, an interval timer keeps every round precise and every rest period honest.
How to Use the Interval Timer
Set your preparation time
Give yourself a few seconds to get ready before the first interval.
Set your work interval
Choose how long each active period lasts.
Set your rest interval
Choose how long you recover between work periods.
Choose your rounds and start
Pick the number of rounds and press Start.
Your interval timer runs automatically through each work and rest period, so you can focus on your workout instead of watching the clock.
Customize Your Interval Workout
Every setting on the interval timer is adjustable, so you can match the timer to any workout format.
| Setting | What it does |
|---|---|
| Preparation | Gives you time to get ready before the first work interval |
| Work | Sets the active exercise duration |
| Rest | Sets your recovery period between intervals |
| Rounds | Determines how many intervals you complete |
| Sound | Provides audio cues at every transition |
Popular Interval Timer Workouts
These work-to-rest formats are the most common starting points for interval training. Load one into the timer with a single click.
20/10 Interval Timer
20 seconds work + 10 seconds rest — the classic Tabata-style format. Use 8–10 rounds.
30/30 Interval Timer
30 seconds work + 30 seconds rest — a balanced format ideal for beginners and steady conditioning.
40/20 Interval Timer
40 seconds work + 20 seconds rest — a popular choice for circuit training and bodyweight workouts.
45/15 Interval Timer
45 seconds work + 15 seconds rest — longer work periods with short recovery for higher intensity.
60/30 Interval Timer
60 seconds work + 30 seconds rest — great for strength circuits and endurance-focused sessions.
Looking for a more structured HIIT workout? Try our HIIT Timer.
Interval Timer for Different Workouts
One interval timer, every training style. Set your work and rest intervals to match the way you train.
HIIT
Alternate short bursts of intense effort with brief recovery. Try 30 seconds work and 15 seconds rest, or open the dedicated HIIT timer.
Circuit Training
Move through several exercises with timed work and rest periods. The 40/20 format is a great starting point for circuits, or open the dedicated circuit timer.
Tabata
The strictest interval protocol: 20 seconds work, 10 seconds rest, 8 rounds. Use the 20/10 preset or our Tabata timer.
CrossFit
Time your metcons, intervals and rest periods. For EMOM and AMRAP formats, dedicated EMOM and AMRAP timers are available, and the CrossFit timer covers every WOD format.
Home Workouts
No equipment needed — just your browser. Pair the interval timer with bodyweight exercises for a complete home session.
Gym Workouts
Use timed rest between sets to keep your strength training consistent and your sessions on schedule, or open the dedicated gym timer and exercise timer.
Running
Structure run/walk intervals or sprint repeats. Set longer work periods and let the audio cues guide you.
Boxing
Simulate rounds and rest periods for boxing, kickboxing or MMA training — or use the dedicated boxing timer.
Why Use an Online Interval Timer?
A free interval timer removes every barrier between you and your workout. There is nothing to download and no account to create — the timer runs directly in your browser, on your phone, tablet or desktop. Set your custom work and rest intervals once, and the timer handles every transition automatically, with clear audio alerts so you never have to look at the screen mid-exercise.
Compared with a stopwatch or a phone clock, an online interval timer keeps your training precise and repeatable. Every work interval lasts exactly as long as it should, every rest period ends on time, and fullscreen mode makes the countdown readable from across the room. Whether you train at home, at the gym or outdoors, this workout interval timer gives your session structure — so you can focus entirely on the effort.
Interval Timer vs. HIIT Timer
An interval timer is a general tool for alternating periods of activity and rest. A HIIT timer is specifically designed for high-intensity interval training.
Use the interval timer on this page when you want full control over your work and rest periods — it fits any training style, from running intervals to strength circuits. Use a HIIT timer when you want a format built around short, maximal efforts and quick recovery, with settings tuned for high-intensity sessions.
Ready for high intensity? Open our HIIT Timer, or compare every format on all workout timers. For a session built around a whole training block rather than a single interval, use the training timer.
Interval Timer FAQ
How to choose the work and rest values in the first place is covered in our guide to work-to-rest ratios.
What is an interval timer?
An interval timer is a timer that alternates automatically between work and rest periods. You set the duration of each interval and the number of rounds, and the timer counts everything down with audio cues at every transition.
How do I use an interval timer?
Set your preparation time, work interval, rest interval and number of rounds, then press Start. The timer moves through every interval automatically until the workout is complete.
Is this interval timer free?
Yes. This online interval timer is completely free — no account, no download and no locked features.
Can I customize work and rest intervals?
Yes. You can set any combination of work time, rest time, preparation time and rounds, or load a quick preset like 20/10 or 40/20 with one click.
Can I use an interval timer for HIIT?
Yes. Set a short, intense work interval and a brief rest period — for example 30 seconds work and 15 seconds rest. For a format built specifically around high intensity, use our HIIT timer.
Can I use an interval timer for home workouts?
Yes. The timer runs in your browser with no equipment needed, so it is ideal for bodyweight circuits and home training sessions.
Does the interval timer work on mobile?
Yes. It works in any mobile browser on iPhone and Android, and the fullscreen mode keeps the countdown easy to read during your workout.
What is a good work-to-rest ratio?
It depends on your goal. A 1:1 ratio (like 30/30) suits general conditioning, a 2:1 ratio (like 40/20) increases intensity, and short-rest formats like 20/10 are for maximal efforts. Beginners can start with more rest and reduce it over time.
Ready to start your workout?
Set your intervals, press Start and begin your workout.
Start Interval Timer