Whats the average weight for a 13 year old female whose 50 Weight for a 15 year old. Body mass index BMI weight kg height m 2. What Should A 15 Year Old Girl Weigh If She Is 5 8 Quora Weight in Pounds Height in Feet inches Body Mass Index BMI Body Mass Index Analysis. . Kilograms Kg Your ideal weight should be between 474 kgs and 717 kgs. BMI healthy weight calculator. The average ideal weight should be 659 kgs. Pounds lb Your ideal weight should be between 1327 and 2008 pounds. Stones and pounds st lb Your ideal weight should be between 9. The average ideal weight should be 8 stones and 45 pounds. The average ideal weight should be 8 stones and 125 pounds. What is the weight for a 15-year-old girl thats 53. This calculator can be used for children and teenagers from 2 years through to 18 years of age. The following table given by the Metropolitan Life Insurance Company provides frame-spec