Ideal Body Weight Calculator
Find your healthy weight range using four established medical formulas — and see how your current weight compares.
Your ideal weight range (average across formulas):
Results by formula:
About ideal body weight formulas
No single formula definitively defines an "ideal" weight — these are statistical estimates developed for clinical use (particularly for medication dosing). Each was derived from different populations, which is why they give slightly different results.
The average of multiple formulas gives a more reliable range than any single estimate. Your healthy weight also depends on muscle mass, bone density, and individual health history — which no formula can capture.
Where the formulas came from
The four most widely used ideal body weight formulas were developed between the 1960s and 1980s, primarily for calculating medication doses in clinical settings rather than as targets for the general public.
Devine formula (1974) — Originally proposed by Dr. B.J. Devine for calculating drug dosages. It became widely adopted in pharmacology and remains the most commonly cited formula in clinical literature.
Hamwi formula (1964) — Developed by Dr. George Hamwi and published in a diabetes management guide. It uses a simple baseline-plus-increment structure and tends to produce slightly higher estimates than Devine for taller individuals.
Robinson formula (1983) — A refinement of Devine, based on a larger dataset. It produces estimates very close to Devine for most heights.
Miller formula (1983) — Generally produces the lowest estimates of the four, and is considered more appropriate for shorter individuals where other formulas can overestimate.
Why your ideal weight isn't a single number
The range produced by these four formulas reflects genuine uncertainty — not a flaw. A realistic healthy weight range spans approximately 10–15 kg for most adults at a given height, depending on frame size, muscle mass, and bone density.
Body composition matters more than weight. Two people at the same height and weight can have very different health profiles depending on their ratio of muscle to fat. Someone with high muscle mass and low body fat may weigh more than their "ideal weight" while being in excellent health, while someone within the ideal range could have poor metabolic health due to high visceral fat.
For a more complete picture of your body composition, the body fat percentage calculator and BMI calculator provide complementary perspectives alongside ideal weight estimates.
How to use this information practically
Use the ideal weight range as a broad reference point rather than a precise target. If your current weight falls within or near the range, it's unlikely to be a primary health concern. If you're significantly above the upper end of the range, even modest weight loss — 5–10% of body weight — is associated with meaningful improvements in metabolic health markers regardless of whether you reach "ideal" weight.
Focus on the behaviours — consistent physical activity, adequate protein intake, quality sleep — rather than the number itself. Weight tends to follow when the fundamentals are in place.