Box breathing: how to do it, and what the research says

How to do box breathing

1. Sit up straight with your feet flat on the floor. Breathe out once, calmly.
2. Breathe in through your nose for 4 seconds.
3. Hold your breath for 4 seconds, loosely.
4. Breathe out slowly for 4 seconds.
5. Hold for 4 seconds with your lungs empty, no straining. Then start the next round.

Each phase is one side of the box. Which way you go around doesn’t matter; what matters is that all four sides take the same time.

One minute in the box

Four rounds, four seconds per side

Breathe along

What the research shows

For something so popular, box breathing has barely been studied. A 2026 systematic review found only a handful of randomized trials, with mixed results.¹ Here are the most useful studies in healthy people:

These studies tested the technique, not the nowa app. The bottom line: in the moment, box breathing works about as well as other calm breathing exercises, but it isn’t special. It doesn’t help everyone equally, and it doesn’t fit every situation. Its biggest advantage is that it’s easy to remember.

The Navy SEAL story

Box breathing was popularized by Mark Divine, a former Navy SEAL. In an essay for TIME, Divine describes first learning breath control through martial arts during SEAL training, and developing box breathing later, after leaving the SEALs, to keep practicing.⁹ There’s no evidence that the SEALs invented it or officially teach it.

Still, the connection isn’t made up. A U.S. Navy training guide for special operations candidates recommends two minutes of box breathing before every workout, specifically to increase alertness. For recovery afterward and for the evening, the same guide recommends a different pattern: in for 5 seconds, out for 7, with no holds.¹⁰

In the military and law enforcement, the same pattern often goes by “tactical breathing” or “combat breathing.” Researchers in police training call it perhaps the most popular breathing technique there, made widely known mainly through books by author Dave Grossman.¹¹ In one study with Canadian soldiers, all of them had already learned it in basic training.¹²

Shorter or longer

Four seconds per side is a suggestion, not a rule. In the Stanford study, each phase lasted anywhere from 3 to 10 seconds depending on the person, and anyone who had to strain was told to shorten all the phases.² If the holds feel hard, use 3 seconds per side. If you get dizzy or find yourself gasping, the box is too big.

So on paper, box breathing, at just under four breaths a minute, is slower than coherent breathing at six. The difference is that your breath stands still half the time.

When box breathing fits, and when it doesn’t

Box breathing is even and easy to count. A lot of people use it before a meeting, a hard conversation, or an exam, because the simple pattern gives your mind something to hold on to, and you can do it with your eyes open. That’s why nowa files box breathing under Focus. There’s more for moments like these in the article on breathing before an exam, a talk, or an interview.

It’s a worse fit right after hard exercise: in one study, it felt much harder than calm breathing without holds.⁷ If counting and holding stress you out, pick an exercise without holds, like the physiological sigh or coherent breathing. And there’s no evidence for sleep: in the Stanford study, sleep didn’t change in any group.² Even the Navy guide prefers a long exhale with no holds for the evening.

Common questions

Do Navy SEALs really use box breathing?

Partly true. It was popularized by former SEAL Mark Divine, who describes developing it after leaving the SEALs. Today, the U.S. Navy recommends it to special operations candidates before workouts. There’s no evidence the SEALs invented it.^{9, 10}

Is box breathing the same as tactical breathing?

Usually, yes. In the military and law enforcement, “tactical breathing” or “combat breathing” generally means the same pattern of four equal phases.¹¹

Which way around the box?

It doesn’t matter. The box is just a picture for four phases of equal length.

Nose or mouth?

There’s no fixed rule. Mark Divine describes breathing in and out through the nose, and the Stanford study asked people to breathe through the nose if possible.^{9, 2} If your nose is blocked, your mouth works too.

How long should I do box breathing?

There’s no proven right amount. Studies used one minute in tense moments and five to six minutes a day over several weeks. The Navy guide suggests two minutes before a workout.^{3, 2, 4, 10}

Box breathing or 4-7-8?

Both include breath holds. In 4-7-8, the exhale is twice as long as the inhale; box breathing is even. Head to head, both raised heart rate variability less than six breaths a minute with no holds, and mood didn’t change with any of them.⁶ More in the article on 4-7-8 breathing.

Does box breathing help you fall asleep?

There’s no evidence for that. In the Stanford study, sleep didn’t change.² For the evening, see the article on breathing exercises for sleep.

Box breathing makes me more anxious and my heart race. Is that normal?

It can happen. Some people feel their heartbeat more clearly while holding their breath, and in a study with physicians, stress even went up slightly for some.⁴ Use shorter sides or an exercise without holds. If the pounding keeps up, or you feel short of breath or dizzy, stop and get it checked by a doctor.