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Equal breathing timer

Breathe in for 4 seconds and out for 4. Each cycle takes 8 seconds, 7.5 breaths a minute, with no holds.

Equal Breathing4-0-4 · 7.5 breaths a minute
0:000 cycles3:00 left
Session length

Cues

Keyboard, while the timer has focus

SpaceStart or pauseEscStopFFocus mode

How to do it

Sit comfortably, with your feet on the floor and your hands in your lap. Breathe in through your nose, and out through your nose or mouth, at the same pace.

  1. Breathe in for 4 seconds.
  2. Breathe out for 4 seconds.
  3. Keep the 2 halves even, with no pause at the top or bottom.

At 4 and 4 you take 7.5 breaths a minute, the quickest of the app's 8 patterns and still slower than typical resting breathing, which is about 9 to 24 breaths a minute.1 If it feels too slow, use 3 and 3 on the custom timer.

Once 4 and 4 feels settled, lengthen both halves by a second at a time. At 5 and 5 it's 6 breaths a minute, which is coherent breathing; at 6 and 6, 5. Stop lengthening when the end of the out breath starts to feel rushed.

The usual mistake is a stall at the top or bottom, followed by a rush to catch up. Turn from in to out smoothly, so the breath keeps moving the whole time, and let the out breath take its full 4 seconds instead of dropping out in the first 2.

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One breath drawn to scale. Blue is in, purple is hold, coral is out.

Other breathing timers

The same timer for every pattern, plus the full comparison.

Box Breathing

4-4-4-4 · 3.8 breaths a minute

Steady and balanced, for stress and focus

When people use it

Equal breathing is the simplest paced pattern to start with: no holds and no ratio to learn. Use it when you want to slow down without counting anything complicated, or as a warm-up before 4-7-8. In yoga it is called sama vritti, a breath of equal lengths.2

The NHS page on breathing for stress teaches an equal breath: in gently while counting from 1 to 5, out the same way, for at least 5 minutes. It says you may not reach 5 at first, and suggests making it part of your daily routine.3

What the research says

A systematic review of slow breathing under 10 breaths a minute included paced breathing at 5.5 to 10 breaths a minute alongside pranayama and HRV biofeedback. It found higher heart rate variability and respiratory sinus arrhythmia during practice, and greater comfort and relaxation in several studies, with the caveat that the studies were small and varied.4

Equal breathing at 4 and 4 is 7.5 breaths a minute, inside that range. The review does not single out equal breathing; it shares the general slow-breathing evidence with the other patterns.

A few studies have compared equal halves with a longer exhale at the same slow rate. In 2014, 47 students breathing at 5.5 breaths a minute showed more heart rate variability with equal halves than with a 4:6 split, and every pattern tested felt more relaxing than their usual breathing.5 A 2024 study found equal halves and a 1:2 ratio gave the same heart rate variability at 6 breaths a minute.6 Both were small studies of students, at a slower pace than 4 and 4.

A 2026 study of sama vritti followed 60 people on hemodialysis, half of whom practiced a 4-4-4-4 version for 5 minutes twice a day for 2 months. They scored better on insomnia and fatigue than the routine-care group, but the study was not randomized or blinded, ran at one site, and its version included holds.2

Questions

Is equal breathing the same as box breathing without holds?

Yes. Box breathing is 4-4-4-4; equal breathing is 4-0-4-0.

What does sama vritti mean?

It is the Sanskrit yoga name for a breath of equal lengths. Some versions add holds of the same length, which makes it box breathing.2

Is 4 seconds in and out enough?

Yes. It is already slower than typical resting breathing.1 Lengthen it only once 4 and 4 feels easy.

Should I breathe through my nose or my mouth?

The NHS page suggests in through the nose and out through the mouth.3 Breathing out through the nose works too and is quieter. Use whichever keeps the 2 halves even.

How is equal breathing different from coherent breathing?

Only in length. Equal breathing is 4 and 4, 7.5 breaths a minute. Coherent breathing is 5 and 5, 6 breaths a minute, close to the rate at which heart rate swings with the breath are largest for most people.1

Can equal breathing help me fall asleep?

A 2026 review of slow breathing before bed found that self-reported sleep improved in 7 of 9 studies, while objective sleep measures were inconclusive.7 None of those studies tested equal breathing. The app's pattern for winding down is 4-7-8.

Can I do equal breathing while walking?

Yes. Match the counts to your steps, or use the timer silently and keep the pace.

Sources

  1. Lehrer, P. M., & Gevirtz, R. (2014). Heart rate variability biofeedback: how and why does it work? Frontiers in Psychology, 5, 756.Typical resting breathing rates, and resonance near 6 breaths a minute
  2. Heydarian, F., Mohammadi, S., Shamsalinia, A., & Arzani, A. (2026). Sama Vritti pranayama breathing exercise on sleep disturbance and fatigue among hemodialysis patients: a quasi-experimental study. Caspian Journal of Internal Medicine, 17(2), 457–463.Sama vritti as a breath of equal lengths, and the 2026 hemodialysis study and its limits
  3. NHS. Breathing exercises for stress. Reviewed 12 June 2026.NHS guidance on counting to 5 in and out, breathing in through the nose and out through the mouth, and practicing for 5 minutes
  4. Zaccaro, A., Piarulli, A., Laurino, M., et al. (2018). How breath-control can change your life: a systematic review on psycho-physiological correlates of slow breathing. Frontiers in Human Neuroscience, 12, 353.The systematic review of slow breathing and its inclusion of paced breathing
  5. Lin, I. M., Tai, L. Y., & Fan, S. Y. (2014). Breathing at a rate of 5.5 breaths per minute with equal inhalation-to-exhalation ratio increases heart rate variability. International Journal of Psychophysiology, 91, 206–211.Equal halves at 5.5 breaths a minute compared with a 4:6 split
  6. Meehan, Z. M., & Shaffer, F. (2024). Do longer exhalations increase HRV during slow-paced breathing? Applied Psychophysiology and Biofeedback, 49(3), 407–417.No difference in heart rate variability between 1:1 and 1:2 at 6 breaths a minute
  7. Eide, E. M., et al. (2026). Slow breathing techniques before bedtime and the effects on sleep: a systematic review. Sleep Medicine Reviews, 102284.The review of slow breathing before bedtime and its inconclusive objective measures

The simplest pattern, on your wrist

BreathKit guides equal breathing on iPhone and Apple Watch, saves each session to Apple Health, and keeps your streak on the Lock Screen.

Download BreathKit on the App Store