Which formulas are used?

Four widely cited equations — Robinson (1983), Miller (1983), Devine (1974) and Hamwi (1964). Each estimates ideal body weight from height and sex, so the spread gives you a healthy range rather than a single number.

Is there one true ideal weight?

No. These formulas predate modern body-composition science and ignore frame size, muscle and age. Treat the range as a guide and combine it with body-fat or BMI measures for a fuller picture.

Is my height data uploaded?

No. All four formulas run entirely in your browser and nothing is sent anywhere or stored.

Why does the calculator give four different answers?

Each formula was derived from a different population and era, so they disagree by a few kilograms. Devine tends to give the lowest figure and Miller the highest. The spread is the point — it is a healthy band, not a single target.

How is ideal weight worked out from height?

Each formula starts with a base weight for the first 5 ft (152.4 cm) of height, then adds a fixed amount per inch above that. For example, Devine adds 2.3 kg per inch over 5 ft for both sexes; the base differs by sex.

What is the Devine formula exactly?

Devine (1974): men 50 kg + 2.3 kg per inch over 5 ft; women 45.5 kg + 2.3 kg per inch over 5 ft. It was originally created for drug-dosing, not weight goals, which is why it reads slightly low.

Should I use this instead of BMI?

Use both. Ideal-weight formulas give a target weight at your height; BMI tells you whether your current weight is healthy. Neither accounts for muscle, so pair them with a body-fat estimate if you train.

Ideal Weight Calculator

Ideal weight calculator — four formulas

This tool estimates your ideal body weight from your height and sex using four classic clinical formulas — Robinson, Miller, Devine and Hamwi. Seeing all four side by side gives you a sensible healthy band rather than one rigid number, which is more honest given that none of them account for frame size, muscle or age. It is a useful sanity check when setting a goal weight.

How it works

All four formulas share the same structure: a base weight covering the first 5 ft (152.4 cm) of height, plus a per-inch addition for every inch above that. The calculator first converts your height to inches over 60, then applies each equation (results convert to lb in imperial mode).

Formula	Men base + per inch	Women base + per inch
Robinson (1983)	52 kg + 1.9 kg	49 kg + 1.7 kg
Miller (1983)	56.2 kg + 1.41 kg	53.1 kg + 1.36 kg
Devine (1974)	50 kg + 2.3 kg	45.5 kg + 2.3 kg
Hamwi (1964)	48 kg + 2.7 kg	45.5 kg + 2.2 kg

Example

A man 178 cm tall is 178 − 152.4 = 25.6 cm = 10.08 inches over 5 ft:

Robinson: 52 + 1.9 × 10.08 = 71.2 kg
Miller: 56.2 + 1.41 × 10.08 = 70.4 kg
Devine: 50 + 2.3 × 10.08 = 73.2 kg
Hamwi: 48 + 2.7 × 10.08 = 75.2 kg

So a healthy target band is roughly 70–75 kg (155–166 lb). Everything is calculated in your browser — nothing is uploaded.