30 second timer — free online countdown

A 30 second timer counts down from 0:30 and rings an alarm at zero. Press Start or the Space bar — it begins instantly, works on phone and desktop, and needs no download or sign-up.

Need repeating 30 second rounds? Use the HIIT or Tabata timer instead of restarting each time.

Thirty seconds is the interval nobody counts accurately in their head. This free online 30 second timer starts on one click, has a silent screen-flash mode for classrooms and offices, and loops its alarm until you dismiss it.

What 30 seconds is used for

Use	Notes
Hand washing	Public-health guidance is at least 20 seconds; 30 gives a comfortable margin.
Plank and wall sit holds	The standard beginner interval before stepping up to 45 or 60 seconds.
HIIT work intervals	30 seconds on / 30 seconds off is the most common beginner ratio.
Espresso extraction	A standard shot pulls in roughly 25-30 seconds from first drip.
Toothbrush quadrants	Four 30 second blocks make up the recommended two minutes.
Speaking and pitch drills	An elevator pitch or classroom answer round fits neatly in half a minute.

Getting the alarm you actually need

Short timers are usually run within arm's reach, so the default chime is enough. In a gym or kitchen, switch to the loud bell; in a classroom or shared office, switch to silent mode and the whole screen flashes red at zero. Whatever you pick, the alarm keeps looping until you press Dismiss, so a 30 second countdown never quietly expires while you're looking away.

Related short timers

Try the 90 second timer for longer holds, the 1 minute timer for the classic round, or the Tabata timer for 20/10 interval work that runs itself.

Frequently asked questions

How do I start a 30 second timer?

Press Start or the Space bar. The 30 second countdown begins instantly and the alarm loops at zero until you dismiss it. Nothing to install, no sign-up.

How long is 30 seconds really?

Half a minute — about the length of one TV advert, the recommended hand-washing time, or a plank hold for a beginner. It feels much longer when you are counting it yourself, which is exactly why a timer helps.

Can I repeat it automatically for intervals?

For back-to-back 30 second rounds use the HIIT or Tabata timer, which loops work and rest intervals with audio cues instead of needing a restart each round.

Does the alarm work with the screen off?

The countdown itself stays accurate because it is anchored to a real end-timestamp. For alerts with the browser closed on a phone, add Tickline to your home screen and allow notifications.

Is there a silent 30 second timer?

Yes — choose silent mode in the controls and the screen flashes red at zero instead of playing a sound. Useful in classrooms, libraries and offices.

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