What is the BOLT-score and what does it reveal about your breathing?
A healthy breathing pattern is the foundation of both physical and mental well-being—but how can you tell whether your own breathing is truly in balance? One quick way to find out is by using the so-called BOLT score. In this article you’ll learn what the BOLT score is, how to measure it correctly, and how breathing exercises can raise your score and improve your health.
What is the BOLT-score?
The BOLT score (Body Oxygen Level Test) is a simple breathing test created by Patrick McKeown, author of The Oxygen Advantage. It provides an indication of your CO₂ tolerance and, by extension, the efficiency of your breathing. Low scores often point to chronic stress, habitual over-breathing, or a disrupted breathing pattern. Higher scores mean your body handles oxygen more efficiently and is therefore more resilient.
Keep in mind: the BOLT score is just one of many self-tests for breathing. It is an indicator, not a diagnosis, and can be influenced by outside factors such as stress, sleep and recent physical activity.
Why your BOLT-score matters
The way you breathe directly affects your energy levels, stress, sleep quality, athletic performance and even digestion. Many people breathe too fast, too shallowly or too high in the chest—often without realising it. The BOLT score gives you a concrete starting point: how efficient is your breathing, really?
How to measure your BOLT-score
The score is the time between a relaxed exhale and the first light urge to breathe in. It is not a maximal breath-hold test, and you should feel no distress.
How to do it:
- Test timing – Do it in the morning, after waking, before coffee or breakfast, and never right after exercise or stress.
- Breathe in and out gently through the nose, as you normally would.
- After an exhale, pinch your nose shut and start a timer.
- The moment you feel the first clear need to inhale, stop the timer and breathe in through the nose.
- Note the seconds: that is your BOLT-score.
💡 Tip: Perform the test three times with a one-minute rest between trials and take the average for a more reliable result.
What your score means:
| BOLT-score (in seconds) | Meaning |
|---|---|
| < 10 sec | Very low – disrupted breathing, often linked to stress or chronic hyperventilation |
| 10–20 sec | Low – signs of an inefficient pattern |
| 20–30 sec | Average – room for improvement |
| > 30 sec | Good – efficient breathing and solid CO₂ tolerance |
A truly healthy pattern starts at 25 seconds or more. The higher your score, the better your body uses oxygen and regulates stress.
How to improve your BOLT-score?
Your breathing muscles and CO₂ tolerance are trainable—much like fitness. Try this simple daily drill:
Sample exercise: 2-5 Breathing
- Inhale through the nose for 2 seconds.
- Exhale through the nose for 2 seconds.
- Hold your breath for 5 seconds.
- Inhale gently and begin the next cycle.
- Continue for 4 minutes.
- Do this exercise, three times a day.
After a week, ease toward a 2-2-10 rhythm (10-second hold after the exhale). Never push to the point of air hunger; the exercise should remain relaxed.
When is the BOLT-score less reliable?
Your score may be temporarily lower if you:
- had a stressful day
- Slept poorly
- Are sick or congested
- Tested at the wrong time (e.g., immediately after exertion)
For accuracy, always test under the same morning conditions and track your progress over several weeks. Use the score as a guideline and, ideally, combine it with professional breath coaching or additional assessments.
The BOLT score is a powerful self-check for breathing quality. It gives you a clear baseline and motivation to pay closer attention to your breath. By incorporating daily breathwork, you can not only raise your score but also lower stress, boost energy and experience deeper inner calm.
As a breathwork instructor I’m happy to help you rebalance your breath with tailored exercises. Feel free to reach out for an introductory chat.