Home Lung Tests

The pulmonary function test at the doctor’s is the safest and best method to identify lung diseases such as COPD or asthma and to monitor their progression. A lung test at home can also be helpful in some cases. Read here when a lung self-test makes sense and what options there are for it.

home lung tests

Can you do lung tests at home?

Yes, you can. If you would like to test the function of your lungs yourself and have a suitable device for this at home, there is nothing to be said against it. It can make sense for COPD and asthma patients particularly to have their lungs tested regularly – as a supplement to the medical check-ups in which the performance of the lungs is monitored.

But even without a test device, you can check your lung function with very simple means. A candle, a balloon or some PET bottles can be used as an aid.


Rapid tests do not replace a medical examination! If you have symptoms such as a chronic cough, rattling breath sounds or mucous sputum, you should always consult a doctor quickly.

 How can you test your lungs yourself?

Peak flow meters, candles, balloons, PET bottles – you have various options at home to test your lung function yourself.

Peak flow measurement

The counterpart to the lung function test at the doctor’s is the measurement at home with the peak flow meter. You can find out how you can use it to test your lung function at home in the article peak flow measurement.

Lungs: test with the candle

This simple method can give you a rough indication of how efficient your lungs are.

How the candle test works:

Sit at a table and place a lit candle on the tabletop one meter away. Now try to blow out the candle. If you can do that, that speaks to a very powerful respiratory organ.

If you are unsuccessful, gradually pull the candle closer to safely, each time trying to blow out the flame. If you only succeed when the candle is less than an arm’s length away, this indicates restricted lung function. Then you should have your lungs examined by a doctor.

Lungs: Test with the balloon

The balloon test is also suitable as a simple lung test to take at home. You need a balloon with a capacity of 10 litres for this. Take a deep breath and inflate the balloon as much as possible with a single breath.

If the balloon is at least 1.5 times the size of your head at the thickest point, your lungs are functioning normally. If it is significantly smaller, your lung volume may be restricted. Then a doctor’s visit is advisable.

Lungs: test with bottles

To test your lung volume, you can also do the bottle test at home. You can use it to roughly determine your vital capacity, i.e., the difference in volume between maximum inhalation and maximum exhalation.

This test is about how much water you can displace in one breath. You need three PET bottles with a volume of 1.5 litres each, a basin filled with water (e.g., a washbasin) and a hose.

Push the first bottle upside down into the pool water so that no water can escape. Now push one end of the hose into the bottle opening under water and put the other end in your mouth.

Take a deep breath, then blow hard into the hose until the bottle is empty. You must not take another breath in between! If the first bottle is empty of water and there is still air in your lungs, continue to hold it and do the same with the second and possibly third bottle – until you run out of air.

You can calculate your vital capacity from the volume of the bottles from which you could expel the water with one breath. For example, if you managed to fill two bottles with one breath, the value is 1.5 x 2 = 3 litres.

For comparison, you can calculate your individual normal volume: To do this, multiply your height by a factor of 2.5. For example, a person who is 1.70 meters tall should have a lung volume (vital capacity) of 1.70 x 2.5 = 4.25 l.

Good indicators but no substitute for a doctor’s visit!

Nowadays it seems most of the populated places in the world in which most of us work and live come with some health warning about our lungs and breathing, from traffic polluted cities like Beijing, hay fever plagued countries like the UK or even sand and dust blasted desert cities like Dubai. Some of the breathing difficulties associated with inhabiting such atmospheres are temporary and go away with no lasting affects once a person moves to some fresh clean air, but others can be more severe and even irreversible. Performing such tests periodically however could serve as an early detection process of a decline in lung function. These simple self-tests do not however replace a visit to the doctor. They only serve as a first, rough indicator of how lungs are performing. People with chronic lung or respiratory diseases should never rely solely on a lung test at home but should always be looked after by a specialist.