Ideal Body Weight Calculator
Devine, Robinson & Miller formulas · shown as a range
Ideal-body-weight formulas estimate a reference weight from height. Each starts at a base for 5 ft (60 in) and adds a fixed amount per extra inch — e.g. Devine (men): 50 kg + 2.3 kg per inch over 5 ft; women start at 45.5 kg. Robinson and Miller use different constants. Because they disagree slightly, this tool shows all three as a range rather than one figure. They ignore muscle, so a lean, muscular person may sit above them.
General reference only, not medical advice or a weight-loss target.
The formulas (inches over 5 ft)
Let x = height in inches − 60 (inches over 5 feet)
Devine men: 50.0 + 2.3·x women: 45.5 + 2.3·x
Robinson men: 52.0 + 1.9·x women: 49.0 + 1.7·x
Miller men: 56.2 + 1.41·x women: 53.1 + 1.36·x (kg)Pair this with the body-fat calculator for a fuller picture of body composition, and the TDEE calculator to plan calories toward a goal.
Frequently asked questions
How is ideal body weight calculated?
The classic formulas start from a base weight for a height of 5 feet (60 inches) and add a fixed amount per extra inch. Devine (men): 50 kg + 2.3 kg per inch over 5 ft; women: 45.5 kg + 2.3 kg per inch. Robinson and Miller use the same structure with different constants, giving a sensible range.
Which ideal-weight formula is best?
There is no single best formula — they were derived for drug dosing, not fitness. Devine is the most widely used; Robinson tends to read a little lower and Miller a little higher. Treating the three together as a range is more useful than trusting any single number.
Is ideal body weight the same as a healthy weight?
Not exactly. These formulas ignore body composition, so a muscular person can be 'over' their ideal weight while being lean and healthy. Use ideal weight alongside body-fat percentage and how you feel, not as a hard target.
Do these formulas work below 5 feet tall?
They are defined for heights of 5 feet and above. Below that, the formulas are extrapolated and become unreliable; some clinicians subtract per inch under 5 ft, but the result should be treated with caution.