The standard height of a 12-year-old girl is 145.1~158.3cm and her weight is 32.42~47.94kg. Girls’ pubertal development is relatively early, most of them start to enter pubertal development at the age of 9~11 years old, and their height will accelerate during this period, which may be around 10 centimeters per year, so the height standard varies greatly depending on the time of pubertal development. Generally, the height of a 12-year-old girl is 145.1~158.3cm and her weight is 32.42~47.94kg. However, height is also affected by genetic and acquired factors, and weight can be affected by nutrition, disease and other factors, and fluctuates more. After a girl enters puberty and develops, she needs to pay attention to supplemental nutrition, participate in more outdoor sports and ensure sufficient sleep, which will help her body grow and develop. If there is any problem, consult a doctor in time.