Guided breathing at your own pace

Pick a pattern, pick a length, and press start. The circle grows while you breathe in, stays put through a hold, and shrinks while you breathe out, with the phase name and the seconds left in it in the middle. Follow the circle rather than the number if you can, and let the count be a guide rather than a target to hit exactly.

Choosing a pattern

Box breathing is the easiest to hold onto when your mind is busy, because every side is the same length. Coherent breathing has no holds at all, which makes it the one to use for longer sits. The 4-7-8 pattern is the most sedating and also the most demanding, so start with fewer rounds than you think you need. The sigh is the fast option: two inhales stacked on top of each other and one long release, which is what your body already does when it settles itself.

Setting your own counts

Custom lets you set the four phases yourself, and a hold set to 0 disappears from the cycle. The useful rule is to make the exhale longer than the inhale. If you want something calming, try 4 in and 6 out with no holds, and lengthen the exhale from there as it gets comfortable.

The cue tone

The tone is off by default. Switched on, it plays a short low sine at each phase change, with a different pitch for in, hold and out, so you can close your eyes or look away from the screen. It is generated in the browser at the moment it sounds. Some browsers will not allow any audio until you have clicked on the page, which is why the tone starts working from the first time you press start.

The basic effect is well supported. Breathing slowly, at roughly five or six breaths a minute instead of the usual twelve to twenty, shifts the balance of the autonomic nervous system towards the parasympathetic side. Heart rate rises slightly on the inhale and falls on the exhale, and stretching the exhale exaggerates that fall, which is why exhale-weighted patterns take the edge off arousal within a minute or two. Controlled trials of slow breathing find reductions in self-reported stress and modest changes in heart rate variability, and the effect is quick enough that you can feel it happen.

The part to be sceptical about is the specific numbers. Box breathing at 4-4-4-4 and 4-7-8 come from traditions and from instructors, not from studies that compared them against other timings and found them better. There is no evidence that 7 is the correct hold or that 8 beats 7 on the exhale. What the research supports is slow breathing with a longer exhale than inhale, in a range that is comfortable for you. Anything within that description will do, so choose by feel rather than by looking for the optimal protocol.

Two practical cautions. Long holds and hard breathing can make you lightheaded, so sit down, keep the effort gentle, and stop if you feel dizzy. And if you have a respiratory or cardiovascular condition, or you are pregnant, treat breathwork as something to raise with a clinician rather than something a web page can prescribe.

Where it fits in a working day

Two minutes before a focus block gives you a clean edge between whatever you were doing and what you are about to do, which is most of the value. It also fits a Pomodoro break better than a phone does, since it leaves you calmer rather than more stimulated. Before something you are nervous about, use the sigh: it is the fastest of the four and needs no setup.