Set work and rest intervals, rounds, sets, a warm-up and a cool-down, then follow a colour-coded countdown with beeps. It runs in this tab and nothing is uploaded.
Interval Timer Online
Set work and rest intervals, rounds, sets, a warm-up and a cool-down, then follow a colour-coded countdown with beeps. It runs in this tab and nothing is uploaded.
Your workout plan and sound settings stay on your device, saved in this browser's local storage. Nothing about your session is sent anywhere.
The Interval Timer turns a workout plan into a run view you can follow from across the room. Enter warm-up, work, rest, rounds per set, number of sets, rest between sets and cool-down, or start from a Tabata 20/10 × 8, HIIT 30/30 × 10, EMOM, boxing or circuit preset. A banner changes colour for work, rest, warm-up and set rest, the countdown shows the current phase, and a strip along the bottom shows the whole workout with a preview of what comes next. Beeps count down the last three seconds of each phase, a higher tone starts work and a lower one starts rest. Time comes from the system clock, so pausing, skipping and background tabs stay accurate. Your plan is remembered in this browser only.
Features
Presets for Tabata 20/10 × 8, HIIT 30/30 × 10, EMOM, boxing rounds and circuit training, each editable
Separate warm-up, work, rest, rounds, sets, rest between sets and cool-down, with the m:ss reading beside every time field
Colour-coded phase banner for work, rest, warm-up, cool-down and set rest
Next-up preview, round and set counter, and a timeline strip of the whole workout
Countdown beeps for the last three seconds, a start tone for work and a warning tone for rest, with volume and mute
Pause, skip a phase or reset at any time, with keyboard shortcuts
Full-screen view readable across the room, a live countdown in the tab title and a screen that stays awake
Your last plan saved in this browser, never uploaded
How to use the Interval Timer
Choose a preset, or enter your own work, rest, rounds and sets
Add a warm-up, a cool-down or a rest between sets if you need them
Press Test sound once so your browser allows audio, then press Start or hit the space bar
Follow the banner and countdown, and use Skip phase, Pause or full screen as you train
Example
Input
Preset: Tabata · 20 s work / 10 s rest · 8 rounds
Output
8 rounds × 20 s work / 10 s rest · 4:00 total
0:00 Work 20 s (Round 1 / 8)
0:20 Rest 10 s
0:30 Work 20 s (Round 2 / 8)
…
3:30 Work 20 s (Round 8 / 8)
3:50 Rest 10 s
Tabata keeps its final rest so the plan totals the classic four minutes. Switch on Skip the final rest to finish at 3:50.
Common errors & troubleshooting
The total is 10 seconds longer than I expected. — The rest after the last round counts toward the total. Turn on Skip the final rest to end right after the last work interval.
There was no sound when the first interval began. — Browsers allow audio only after you interact with the page. Press Test sound once, check the volume and that Sound cues is on, then press Start.
I cannot edit the plan while the timer is running. — The plan is locked during a workout so the clock and the schedule stay in step. Press Reset to unlock it, make your changes and start again.
The beeps came late after I switched to another tab. — Browsers slow timers in background tabs. Keep the timer in view, or use full screen, for exact beeps; the screen stays awake while it runs.
Frequently asked questions
What is Tabata 20/10 in the Interval Timer?
Tabata is eight rounds of 20 seconds of all-out work, each followed by 10 seconds of rest, which adds up to four minutes. The Tabata preset sets exactly that, including the final rest, so the total reads 4:00.
What is the difference between HIIT and EMOM intervals in the Interval Timer?
HIIT alternates hard work and rest periods of fixed length, such as 30 seconds on and 30 off. EMOM means every minute on the minute: a new round starts each minute and you rest for whatever time the work leaves over. For EMOM, set work to 60 seconds with no rest, or split the minute, such as 40 seconds of work and 20 of rest.
Does the last rest play at the end of an Interval Timer workout?
The Tabata preset keeps it so the plan lasts four minutes. The HIIT, EMOM, boxing and circuit presets drop it, because ending on a rest wastes time. The Skip the final rest switch changes this for any plan.
When do the beeps play in the Interval Timer?
A short beep sounds for each of the last three seconds of every phase, a higher tone starts each work interval, a lower tone starts each rest or cool-down, and a three-note finish plays at the end. The Sound cues switch mutes all of it.
Does the Interval Timer stay accurate in a background tab?
The elapsed time comes from the system clock, so the countdown is right whenever you look. Browsers can delay the beeps of a hidden tab, so keep the timer in view or in full screen during a workout.
How long can a session in the Interval Timer be?
Each phase can last up to 60 minutes, and a plan can have up to 100 rounds in each of up to 50 sets, so even very long workouts fit. The total is shown beside the plan summary before you start.
Related tools
Stopwatch — A stopwatch with laps, splits and CSV export that keeps true time in a background tab.
Countdown Timer — Set hours, minutes and seconds and get an alarm when time is up — presets, full screen and a share link.
Pomodoro Timer — Focus and break cycles with long breaks, session counts and a local daily tally.