Ideal weight calculator

Four classic ideal-weight formulas side by side, plus the healthy BMI range.

Formula Health & fitness

Average of the four formulas

Rounded for display

Devine (1974): ≈ 70.5 kg
Robinson (1983): ≈ 68.9 kg
Miller (1983): ≈ 68.7 kg
Hamwi (1964): ≈ 72.0 kg
BMI 18.5 at your height: ≈ 56.7 kg
BMI 24.9 at your height: ≈ 76.3 kg

How it works

Each formula starts from a base weight at 5 feet (152.4 cm) and adds a fixed amount for every inch above that. They were developed for clinical uses such as drug dosing, not as personal targets.

The four formulas give different answers, so the average is shown first, with the weight range for a BMI of 18.5 to 24.9 for comparison. Frame size, muscle and age are not taken into account.

This is a general estimate, not medical advice. For personal guidance, speak to a doctor or registered dietitian.

Formula

Devine: men 50 kg + 2.3 kg per inch over 5 ft; women 45.5 kg + 2.3 kg
Robinson: men 52 kg + 1.9 kg; women 49 kg + 1.7 kg
Miller: men 56.2 kg + 1.41 kg; women 53.1 kg + 1.36 kg
Hamwi: men 48 kg + 2.7 kg; women 45.5 kg + 2.2 kg

Worked example

A man 175 cm tall is 68.9 inches, 8.9 inches over 5 feet. Devine gives 50 + 2.3 × 8.9 = 70.5 kg, Robinson 68.9 kg, Miller 68.7 kg and Hamwi 72.0 kg, an average of 70.0 kg.

Questions people ask

Which ideal weight formula is best?

None is best for everyone. Devine is the most widely used in medicine; all four are rough guides based on height and sex only.

Why do the formulas disagree?

They were fitted to different data at different times, so the base weights and the amounts added per inch differ.