Puberty happens at a different time for everyone. There is no way to know when it will start for you. Puberty occurs when hormones start making changes in your body. Girls usually get a head start on puberty because they usually start these changes between the ages of 8 and 13. Most boys, on the other hand, don’t begin until between the ages of 9 and 14. If you are worried about when you will start puberty you can talk to your doctor for more information.