How Do You Determine the Correct Body Weight Based on Height and Age? has an ideal weight calculator based on height, age and frame size. Body mass index, or BMI, is commonly used to determine a normal weight range, but it only uses height for adults; age is only a factor for children and teens.

On the home page, placing the cursor over the Miscellaneous label causes a drop down menu to appear. Click on Discover Your Ideal Weight, and enter the person's current weight, height, frame size, gender and age. The calculator provides a BMI, a normal weight range based on the BMI formula, and two ideal weights, one that takes into account age and frame size and another that doesn't.

Weight charts list normal weight ranges for each height and frame size. However, weight charts and formulas such as BMI are limited because they don't account for body composition. An athlete with a large amount of muscle mass could have a similar BMI to an overweight, inactive person. Calculating body fat percentage is a more effective method to determine overall health, as it's the only measurement that gauges overall body composition. There are multiple methods of calculating body fat percentage that vary in accuracy, including skin calipers, bioelectrical impedance and hydrostatic weighing.