Ideal weight, large frame
This page applies a large frame adjustment to the three ideal weight formulas for a woman at 5 ft 8.5 in.
How it works
Devine, Robinson and Miller each start from a base weight at 60 inches and add a set number of kilograms for every inch above 60. The page runs all three and shows the lowest and highest as your range. For a woman at 5 ft 8.5 in the height over 60 is 8.5 inches.
Worked example
Take a woman who is 5 ft 8.5 in tall. That is 8.5 inches over 60. Devine: 45.5 + 2.3 × 8.5 = 65.05 kg, or 143 lb. Robinson: 49 + 1.7 × 8.5 = 63.45 kg, or 140 lb. Miller: 53.1 + 1.36 × 8.5 = 64.66 kg, or 143 lb. The range is 140 to 143 lb. For a large frame, take 10 percent on top of the range. 139.88 × 1.1 = 153.868 lb and 143.41 × 1.1 = 157.751 lb. The large frame range is 154 to 158 lb.
Common questions
Why do the formulas give different answers?
Each uses its own base weight and its own amount per inch. The gap grows as height moves away from 5 feet. For a woman at 5 ft 8.5 in the gap between the lowest and highest is 3 lb.
Do these formulas account for muscle or frame size?
No. They use only height and sex. Someone with a large frame or a lot of muscle can be healthy well above the range. For a woman at 5 ft 8.5 in the range of 140 to 143 lb is a starting point, not a limit.
Is 140 to 143 lb a target I must hit?
No. It is a starting reference for a woman at 5 ft 8.5 in. Your doctor can tell you what weight suits your own health. For a woman at 5 ft 8.5 in the range spans 3 lb.
What if I am under 5 feet tall?
The formulas were written for heights of 5 feet and over. Below that the calculator uses the base weight. Treat the result as rough. For a woman at 5 ft 8.5 in the formulas add 8.5 inches above the 60 inch base.
How does this compare with BMI?
A healthy BMI range also gives a weight range for your height. The two often overlap but they are not the same, because BMI ignores sex while these formulas use it. For a woman at 5 ft 8.5 in a healthy BMI is 123 to 166 lb, against 140 to 143 lb here.