Interval timer
Work and rest roundsBeeps at every changeFull screen
Get ready
Space to start or pause, R to reset, F for full screen.
Pick a preset or type your own times, then press Start. Each phase has its own color, orange for work, green for rest and blue for warm-up and cool-down, so you can tell where you are from across the room. Three short ticks count down the last seconds of every phase, a high double beep starts the work and a low tone starts the rest.
The presets
| Preset | Work | Rest | Rounds | Rounds take |
|---|---|---|---|---|
| Tabata 20/10 | 20 s | 10 s | 8 | 3:50 |
| 30/30 | 30 s | 30 s | 10 | 9:30 |
| 40/20 | 40 s | 20 s | 10 | 9:40 |
| 45/15 | 45 s | 15 s | 10 | 9:45 |
| EMOM 10 min | 60 s | none | 10 | 10:00 |
Every preset starts with 10 seconds to get ready, and none rests after the last round, because there’s nothing left to rest for. That’s why 10 rounds of 30/30 take 9:30 rather than 10:00.
Tabata is 20 seconds of hard work and 10 seconds of rest, eight times. It takes its name from Izumi Tabata, whose 1996 study used that pattern on exercise bikes. With the get-ready, the preset runs exactly 4:00.
30/30, 40/20 and 45/15 are common circuit splits, read as work then rest. They all fit a minute per round, and the work share goes up from half to three quarters.
EMOM means every minute on the minute: start your reps when the minute begins and rest for what’s left of it. The preset has no rest phase; it beeps at the top of each minute for 10 minutes.
Custom intervals
Type any work and rest time from 1 second to an hour, up to 99 rounds, with an optional warm-up and cool-down. A 5-minute warm-up, 12 rounds of 40 seconds on and 20 off, and a 3-minute cool-down come to 19:40: 5:00, then 11:40 of rounds, then 3:00. The setup goes into the address as you type, so the link /interval-timer?work=40&rest=20&rounds=12&warmup=300&cooldown=180 opens that exact workout.
Space starts and pauses, R resets and F goes full screen, where the background takes the phase color. While it runs, the timer asks your device to keep the screen on.
Questions people ask
What is a Tabata timer?
A Tabata timer runs 20 seconds of work and 10 seconds of rest, eight times, which makes four minutes. On this page, pick Tabata 20/10 and press Start. You get 10 seconds to get ready, then eight rounds; the rest after the last round is left out, so the whole thing takes exactly 4:00.
What does EMOM mean?
Every minute on the minute. At the start of each minute you do a set number of reps, then rest for whatever is left of that minute. The EMOM preset beeps at the top of each minute for 10 minutes; change Rounds to make it longer.
Will it keep beeping if my phone screen turns off?
Not reliably. Phones pause web pages soon after the screen locks, and a paused page can’t beep. While the timer runs it asks the phone to keep the screen on, which recent versions of Chrome, Edge and Safari allow. In a background tab on a computer it keeps beeping on time.
How long should work and rest intervals be?
There’s no single right split. More rest than work, or an even 30/30, is easier to keep up; less rest, like Tabata’s 20/10, is harder. Pick one you can finish with good form and adjust from there. If you’re new to exercise or have a health condition, check with a doctor before hard intervals.
How do I share my interval setup?
Set it up and press Copy link. The numbers are in the address, like countdownx.net/interval-timer?work=40&rest=20&rounds=12, so anyone who opens it gets the same workout ready to start.
Other timers
For a single countdown, use the countdown timer. The stopwatch times laps and runs, and the alarm clock rings at a time of day while the tab is open. Training for a race on a set date? The Countdown app for iPhone counts down the days to it.