Healthy Weight Calculator
Find the weight range that puts you in the World Health Organization healthy BMI band for your height, in kilograms or pounds.
Healthy weight range — kg
56.7 – 76.3 kg
- Lower bound (BMI 18.5) — kg
- 56.7
- Upper bound (BMI 24.9) — kg
- 76.3
The healthy range comes from the WHO adult BMI band 18.5–24.9, solved for weight at your height: weight = BMI × (height in metres)². It is population guidance, not a personal target. The band is not valid in pregnancy, childhood, or for highly muscular athletes — muscle is denser than fat and can push BMI into the overweight band without excess body fat.
How to use this calculator
Pick metric or imperial and enter your height. The calculator returns the lower and upper bound of the healthy weight range for that height — the weights that sit at BMI 18.5 and BMI 24.9 respectively. Optionally enter your current weight to see where it falls relative to the range: under, within, or over, with the kilograms or pounds you would need to shift to reach the nearest edge of the band.
How the calculation works
The World Health Organization defines a healthy adult BMI as 18.5 to 24.9. Rearranging the BMI formula (BMI = kg ÷ m²) for weight gives the band edges: healthy_min = 18.5 × height_m² and healthy_max = 24.9 × height_m². Heights in inches are converted with the NIST-exact factor 1 in = 0.0254 m, and weights in pounds with 1 lb = 0.45359237 kg, so the answer is identical in either unit system. The band applies to adults aged 18 and over and is not valid in pregnancy, in childhood, or for highly muscular athletes — muscle is denser than fat and can push BMI above 25 without indicating excess body fat.
Worked example
An adult who is 1.75 m tall. Height squared is 1.75 × 1.75 = 3.0625 m². Lower bound = 18.5 × 3.0625 = 56.66 kg, rounded to 56.7 kg (≈ 124.9 lb). Upper bound = 24.9 × 3.0625 = 76.26 kg, rounded to 76.3 kg (≈ 168.1 lb). A 70 kg current weight gives BMI 70 ÷ 3.0625 = 22.9, comfortably inside the band — no shift needed.
Frequently asked questions
What weight range is considered healthy?
The World Health Organization classifies adult BMI 18.5 to 24.9 as the healthy band. For a given height, that translates to a specific weight interval: at 1.70 m the healthy range is roughly 53.5–72.0 kg (≈ 118–159 lb); at 1.80 m it is 60.0–80.7 kg (≈ 132–178 lb). The range scales with the square of height, so taller people have a wider healthy interval in absolute kilograms or pounds.
Is this the same as a BMI calculator?
It uses the same WHO BMI band but inverts the question. A BMI calculator asks "given my weight and height, what is my BMI?" and then tells you which band you are in. A healthy weight calculator asks "given my height, what weight would put me at the edges of the healthy band?" — useful if you want a target range rather than a single number.
Why are imperial and metric results sometimes off by 0.1?
The underlying maths is identical: imperial inputs are converted to metres and kilograms using NIST-exact factors (1 in = 0.0254 m, 1 lb = 0.45359237 kg) before the formula is applied, and the metric result is converted back for display. Tiny differences come from rounding to one decimal place at the end — if your reported height is rounded to the nearest inch or half-inch, the converted metre value will be slightly off and the band edges shift by a tenth of a kilogram or pound.
Is the healthy weight range different for men and women?
The WHO adult BMI band is sex-neutral, so the calculated range is identical for men and women of the same height. Women carry slightly more essential body fat than men at the same BMI, but the band does not adjust for that. For a sex-aware target, look at body fat percentage or lean body mass instead of weight alone.
Can I use this during pregnancy?
No. BMI and the WHO healthy band are not valid in pregnancy — your weight includes the foetus, placenta, amniotic fluid, and increased blood volume, none of which are body composition. Clinicians track gestational weight gain against pre-pregnancy BMI guidelines (such as the Institute of Medicine ranges) rather than computing BMI on current weight.
What about children and teenagers?
Children and adolescents are assessed against age- and sex-specific BMI percentile charts (CDC in the US, WHO growth standards internationally), not the adult 18.5–24.9 band. Plugging a teenager into this calculator will return a numeric range, but the range will not match clinical paediatric guidance — use a BMI-for-age tool instead.