NanoTimer
App Store

45 second timer

A forty-five second timer with a sound at the end. Forty-five seconds is the work half of the most common circuit format there is: 45 on, 15 off.

00:45
RingBar
Presets

Take it with you in the app

This tool runs in your browser. Want it on your phone, with voice cues, background timing and a real alarm? Open the same tool in NanoTimer.

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How it works

  1. Tap Start and work until the tone.
  2. In a 45/15 circuit this is the working interval; the fifteen second timer is the rest.
  3. It also suits a long plank or a held stretch, where the last ten seconds are the ones that count.
  4. For the full circuit with rounds, use the interval timer instead of restarting this.

Frequently asked questions

Why is 45/15 so common?
Because it divides a minute cleanly and leaves just enough rest to keep form without letting the heart rate drop. It is long enough to get real work done in a station and short enough to keep a class moving.
Is forty-five seconds long for a plank?
It is a reasonable target once thirty seconds feels easy. What matters more than the number is that the form holds all the way to the tone; a shorter, straighter plank beats a longer sagging one.
Can I run a whole circuit here?
This page is one countdown. For a circuit that alternates work and rest across rounds, the interval timer handles it, and the app speaks each phase so you do not have to look.

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