How many hours a day should I practice?

That is the evergreen question of every beginner. But the answer is more complicated than only to say: ” Practice at least 4 hours every day…or 6…or practice the whole day, or you will not show any progress! In my opinion, it is not 100% true.

Everyone is unique, and so is the physical and mental capability of every person. When we look at a musician while she or he plays her or his musical instrument, most of the time, it looks so graceful and elegant. Hard to believe that playing any musical instrument is hard physical and mental work.

The psychological and physical background of practising

The main question is not, how many hours should someone practice a day? The appropriate question is, how many minutes the person is capable of focusing on a task intensely? The answer is very sobering: The duration of focusing is dependent on the age of the person. We can measure it in minutes only.
The attention span of a typical child at 6 is about 12-15 minutes. To calculate how long a student in front of me will be capable of maintaining focus on a given task is easy. Experts of childhood development are recommending to multiply 2-3 minutes with the age of the child.
For this reason, I recommend for children under the age of 10 two times 30 minutes of music lesson in a week, rather than 1x 60 minutes.
Adults can maintain focus for a longer time, but there is also a limit: 90 minutes, then must follow a break of at least 15 minutes, to be able to continue working effectively.

Besides the cognitive development of a person, physical condition and stamina are determinative in how long a practise session can last.

Playing a musical instrument is a physical strain. When you play the piano, the violin, the trumpet, drums, etc., you use muscles and joints in your body, which you usually barely even think on. These body parts need to be warmed up and trained to be ready to coordinate your movements. Practising is not just focusing on getting the correct pitch. For producing the right sound on your musical instrument, you use your whole body.
We can say that practising music is an intense workout for the body and brain.

Let us go back to the original question now: how many hours a day should I practise?

In my opinion, in this matter, the quality and the regularity is more important than the quantity.
As you could read above, our mental and physical capacity is finite. To improve this capacity, without overdoing anything, it is highly recommended to work out a good practice routine and follow it.

Do shorter sessions, focusing on a particular task in the piece.
If we take the ability to focus as a basis, then we can say that a 45 minutes practice session for an adult person can be sufficient for effective practising. We can take it as a minimum of time per day for an adult person. The rest is up to you. If you have more time, practice more. But always keep in your mind your capabilities.

For children, the time of efficient practising based on age, interest, cognitive and physical development. Here applies the same rule: plan regular and shorter practice sessions for children, rather than irregular and too long ones. Long sessions by most of the children are usually contra-productive.

How often should I practice?

Regularity is one of the main keywords when we talk about practising the piano, the violin, or any other musical instrument. Everyday practising would be the optimal scenario if someone would like to reach those goals very quickly. Make practising a daily routine, like your morning coffee or brushing your teeth. Have a regular time window for it in your day and try to stick with it. When only 10 minutes or 15, but stick with your daily routine.
Think about it as a sport. An athlete who would like to win the Olympic games must be training every day, or the muscles get stiffened again, and all the hard work was in vain. The same can happen to your muscles too, and after missed practise sessions, you will have difficulties getting back to the level where you have finished.