Ideal Weight
What's a healthy weight for your height?
Five classic formulas, two BMI standards, four goal contexts, and a lean-mass-aware target. No single ideal weight exists — we show you the range, then refine by what you're optimising for.
WHO global: normal 18.5–24.9.
Goal-tuned target weight
Health / longevity · BMI 22 midpoint — lowest all-cause mortality · WHO
Healthy range: 53.5–72.0 kg
Multi-formula comparison
Spread: 3.1 kg
Devine
1974 · clinical drug dosing
65.9 kg
Robinson
1983 · Devine refinement
65.2 kg
Miller
1983 · most generous, modern
66.0 kg
Hamwi
1964 · dietitian standard
66.7 kg
BMI midpoint
WHO healthy target
63.6 kg
The 5-formula spread of 3.1 kg shows there's no single "ideal weight." Average across formulas: 65.5 kg. Devine was originally a drug-dosing formula, not a health target — Miller is the most modern.
Healthy weight range — dual standard
53.5 – 72.0 kg
53.5 – 66.2 kg
WHO's universal range over-counts South Asian users as "healthy" when they already carry elevated visceral fat — about 45% of normal-WHO-BMI South Asians show the "thin-fat" phenotype (Kanaya 2014). Use Asia-Pacific thresholds if you're of native South Asian descent.
No single ideal weight exists.
These formulas are decades old (Devine 1974 was for drug dosing, not health) and assume average body composition. Healthy weight is a range, not a number, and depends on body composition, ethnicity, age, and what you're optimising for.
Skinny-fat is real.
BMI 21 with 28% body fat is metabolically worse than BMI 26 with 15% body fat. Targeting only "ideal weight" without body composition context can perversely produce a worse outcome. Pair with the body fat and waist-to-height tools.
How it works
Five formulas in parallel: Devine (1974, clinical drug-dosing origin), Robinson (1983), Miller (1983), Hamwi (1964), and the BMI midpoint at your selected target BMI. Spread is shown as a band, not collapsed to a single number.
Dual BMI standard: WHO global 18.5–24.9 vs Asia-Pacific / ICMR 18.5–22.9. South Asians carry 3–5% more body fat and substantially more visceral fat at the same BMI (MASALA, MESA studies) — so the Asia-Pacific cap is the correct anchor for native South Asian users.
Goal-tuned target BMI: Health (BMI 22, lowest all-cause mortality) · Fat loss (BMI 21) · Aesthetics (BMI 23 with low body fat) · Performance (BMI 24 accommodates muscle mass).
Lean-mass-aware target (optional with body fat %): given your current LBM, what weight reaches a healthy target body fat % (15% men / 22% women) while preserving lean tissue? More useful than formula targets for muscular and athletic users.
Frequently asked questions
Is there one true 'ideal weight'?
No — there's a range, and it depends on what you're optimising for. The classic formulas (Devine, Robinson, Miller, Hamwi) typically disagree by 5-8 kg at the same height. Devine 1974 was originally a clinical drug-dosing formula, not a health target. Miller is the most modern. The BMI midpoint at your chosen target BMI is usually the most defensible single number.
Why use the Asia-Pacific BMI standard?
WHO's universal 18.5-24.9 range was derived on European reference populations. MASALA and MESA studies show South Asians carry 3-5% more body fat and substantially more visceral fat at the same BMI — about 45% of normal-WHO-BMI South Asians have the 'thin-fat' phenotype (metabolically unhealthy at normal weight). ICMR / WHO Asia-Pacific drops the upper threshold to 22.9 to reflect this.
What does 'ideal for what?' mean?
Different goals point at different BMI sweet spots. Health/longevity is BMI 22 — lowest all-cause mortality in pooled meta-analyses. Fat loss aims at BMI 21 (lower healthy band). Aesthetics targets BMI 23 with low body fat. Performance/strength accommodates muscle mass at BMI 24. A 90 kg / 6 ft lifter at 12% body fat will read 'overweight' by classical formulas but is at healthy BMI 23 for a performance physique.
Does ideal weight account for muscle and body composition?
Not in the classical formulas. They use only height and sex, so two people at the same 'ideal' weight can look radically different — one lean and muscular, one skinny-fat. That's why the tool offers the optional lean-mass-aware target: enter your body fat % and we compute the weight needed to reach a healthy body fat (15% men, 22% women) while keeping your current lean mass.
Why was Devine's formula made in the first place?
It was created by B.J. Devine in 1974 as a pharmacist's tool for dosing aminoglycoside antibiotics safely — drug doses had to scale with lean mass, which Devine approximated from height. It was never validated as a health or aesthetic target. Robinson and Miller refined it later with insurance-table data, but all four formulas assume average body composition.
What's skinny-fat and how do I avoid it?
Normal-weight obesity: BMI 21-23 with body fat above ~25% men / 32% women. Metabolically worse than higher BMI with low body fat (Wildman 2008, NHANES). Targeting only 'ideal weight' without body composition can perversely produce skinny-fat. Combine this tool with our body-fat and waist-to-height calculators, and resistance-train to preserve / build lean mass during weight changes.
How accurate is the lean-mass-aware target?
It assumes you preserve your current lean mass while losing only fat — achievable with adequate protein (1.8-2.4 g/kg LBM) and resistance training during the cut. Without those, lean mass also falls, so the target overestimates the achievable weight. Recompute every 4-6 weeks as composition changes.