At the age of 17, if the epiphyses are not closed, boys can usually grow about 3 to 10 centimeters taller, and girls can grow another 3 to 5 centimeters taller, but if the epiphyses are closed, they cannot grow any taller. The epiphyses are usually cartilages that help the long bones to grow, and they will close as you get older, and you will not grow any taller. If the epiphyses are not closed, you can still grow taller. Generally, you can decide how much you can grow taller based on nutritional factors, such as good nutrition, a proper diet, and enough sleep. Usually, at the age of 17 years old, boys can still grow 3 to 10 centimeters taller, and girls can still grow 3 to 5 centimeters taller. If the epiphysis is completely closed at the age of 17, it is usually not possible to grow taller, mainly due to the closure of the human body’s bones, can no longer grow vertically and thus can not grow taller. How much you can grow at 17 years old can be determined after you go to the hospital for a checkup to see if your epiphyses are closed or not.