Ideal Weight Formulas Compared: Devine vs Robinson vs Miller vs BMI Range

'How much should I weigh?' has four classic answers — literally. The ideal weight calculator shows all of them side by side. Here is where each formula comes from and which applies when.

The Four Formulas (for a 170 cm man, for example)

| Formula | Formula (men) | Result at 170 cm | |---|---|---| | Devine (1974) | 50 kg + 2.3 kg per inch over 5 ft | 65.8 kg | | Robinson (1983) | 52 kg + 1.9 kg per inch over 5 ft | 65.3 kg | | Miller (1983) | 56.2 kg + 1.41 kg per inch over 5 ft | 66.3 kg | | BMI range (WHO) | 18.5-24.9 × height² | 53.5-72.0 kg |

For women, the constants drop (Devine: 45.5 kg base) — the full tables are on the calculator page.

Where Each Came From (and Why It Exists)

Devine was created for medication dosing (digoxin, gentamicin) — drugs that distribute into lean mass. It remains the clinical standard for chemo dosing and renal clearance (Cockcroft-Gault uses it). It was never a wellness target.

Robinson and Miller refined Devine against actual height-weight mortality tables — slightly different constants, same intent: a single number for clinical work.

The BMI range is the epidemiological band where mortality curves bottom out in population data. It's wide (18.5 kg spread at 170 cm) because healthy bodies vary — composition, ancestry, build.

Which One Applies to You?

• For medication questions: the clinical team uses Devine (or adjusted body weight if your actual weight exceeds it 20%+)
• For a personal target: the BMI band, intersected with your body composition — a 170 cm lifter at 80 kg (BMI 27.7) can be leaner than a sedentary 68 kg
• The honest anchor: waist-to-height ratio under 0.5 predicts metabolic risk better than any weight formula

People Also Ask (PAA)

What is my ideal weight for my height? The healthy BMI band (18.5-24.9) spans a wide range: for 170 cm, 53.5-72 kg; for 165 cm, 50.4-67.7 kg. Within the band, build and composition decide. The calculator shows all four formulas plus your BMI band.

Why do ideal weight calculators give different numbers? Different formulas answer different questions: Devine was built for drug dosing, Robinson/Miller for mortality data, BMI for population statistics. None measures YOUR body — composition metrics (body fat %, waist ratio) complete the picture.

Is the Devine formula still used? Yes — it remains the standard basis for medication dosing calculations (chemotherapy, antibiotics, renal clearance formulas) and for tidal volume settings in mechanical ventilation. Clinical utility, not aesthetics.

What weight is healthy for a muscular person? BMI overestimates fatness in muscular builds (BMI 27-30 with low body fat is common in athletes). Better markers: body fat percentage (via the body fat calculator), waist-to-height <0.5, and metabolic labs.

The Bottom Line

Use the ideal weight calculator to see the range, then judge by composition: body fat %, waist, energy, and labs. Weight is a coordinate, not a verdict.

Last reviewed: September 2026. Educational content — individual targets belong with your clinician.