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BMI Calculator
Work out your body mass index from height and weight — in pounds and feet or kilograms and centimetres — with the WHO category bands and the healthy weight range for your height. A screening number, not a diagnosis.
Short answer
BMI = weight ÷ height²(or 703 × lb ÷ in² in US units). At 5'10" and 160 lb that's 23.0 — normal weight; the WHO adult bands are under 18.5 underweight, 18.5–24.9 normal, 25–29.9 overweight, 30+ obesity. It's a screening number that can't tell muscle from fat — enter your numbers below and read it as a starting point, not a verdict.
BMI = 703 × lb ÷ in²
Your BMI
23.0
- Category
- Normal weight
- Normal-BMI weight for this height
- 129–174 lb
A screening estimate for adults — not medical advice, and blind to muscle vs fat.
BMI chart and healthy weight by height
BMI by height and weight
| Height | 120 lb | 140 lb | 160 lb | 180 lb | 200 lb | 220 lb |
|---|---|---|---|---|---|---|
| 5 ft 0 in | 23.4 | 27.3 | 31.2 | 35.2 | 39.1 | 43 |
| 5 ft 2 in | 21.9 | 25.6 | 29.3 | 32.9 | 36.6 | 40.2 |
| 5 ft 4 in | 20.6 | 24 | 27.5 | 30.9 | 34.3 | 37.8 |
| 5 ft 6 in | 19.4 | 22.6 | 25.8 | 29 | 32.3 | 35.5 |
| 5 ft 8 in | 18.2 | 21.3 | 24.3 | 27.4 | 30.4 | 33.4 |
| 5 ft 10 in | 17.2 | 20.1 | 23 | 25.8 | 28.7 | 31.6 |
| 6 ft 0 in | 16.3 | 19 | 21.7 | 24.4 | 27.1 | 29.8 |
| 6 ft 2 in | 15.4 | 18 | 20.5 | 23.1 | 25.7 | 28.2 |
BMI = 703 × pounds ÷ inches². Under 18.5 underweight · 18.5–24.9 normal · 25–29.9 overweight · 30+ obesity.
BMI categories (WHO/CDC adult bands)
| Category | BMI range |
|---|---|
| Underweight | below 18.5 |
| Normal weight | 18.5–24.9 |
| Overweight | 25–29.9 |
| Obesity | 30 and above |
Adult bands; they do not apply to children, and interpretation differs for some ethnic groups and for very muscular builds. A screening measure, not a diagnosis.
What BMI can and cannot tell you
BMI earns its place by being universal: two numbers anyone knows, one formula, comparable across whole populations — which is exactly what it was designed for. What it cannot do is see inside the number: muscle and fat weigh the same to it, distribution (the waistline that actually predicts risk) is invisible, and the bands shift meaning with age and ancestry. Used honestly — as a first screen, alongside how you feel, your waist measurement, and a clinician's judgment — it's useful. Used as a verdict, it misleads in both directions.
How we calculate this
The standard adult BMI formula, in both unit systems:
- Metric. BMI = weight in kilograms ÷ (height in metres)². 70 kg at 1.75 m → 22.9.
- Imperial. BMI = 703 × weight in pounds ÷ (height in inches)². 160 lb at 70 in → 23.0.
- Category & healthy range. the result is placed in the WHO/CDC adult bands, and the healthy-weight range inverts the formula: 18.5–24.9 × height².
Assumptions
- Adults only — children and teens use age- and sex-specific percentiles instead of these bands.
- BMI cannot distinguish muscle from fat, so athletes often score 'overweight' while lean; waist circumference and body-composition measures add the missing context.
- Category cut-offs differ for some populations (e.g. lower thresholds are recommended for some Asian populations).
- This is an educational screening number, not medical advice — decisions about weight and health belong with a clinician.
Sources
Last reviewed: July 22, 2026
Frequently asked questions
How is BMI calculated?+
Weight divided by height squared: kilograms ÷ metres² in metric, or 703 × pounds ÷ inches² in US units — the 703 is just the unit-conversion constant, both give the same number. 70 kg at 1.75 m is a BMI of 22.9; 160 lb at 5'10" is 23.0. The calculator handles both systems and shows the WHO category alongside the number.
What is a normal BMI?+
The WHO/CDC adult bands are: under 18.5 underweight, 18.5–24.9 normal, 25–29.9 overweight, and 30+ obesity (with obesity further divided into classes at 35 and 40). These are population screening ranges drawn from health-outcome statistics — being just over a line is not a medical event, and the healthy-weight range for your height gives a more useful target than a single number.
Is BMI accurate for everyone?+
No, and it doesn't claim to be. BMI only knows height and weight, so it can't tell muscle from fat — many athletes class as 'overweight' while lean — and it misjudges at the extremes of height, in older adults who've lost muscle, and during pregnancy. Cut-offs also differ by population: lower thresholds are recommended for some Asian populations. It's a quick screening number; waist circumference and body-composition measures add what it misses.
What is a healthy weight for my height?+
Invert the formula: multiply 18.5 and 24.9 by your height in metres squared. At 5'10" (1.78 m) that's roughly 129–174 lb (59–79 kg); at 5'4" roughly 108–145 lb. The per-height pages on this site show the band for common heights, and the calculator computes it exactly for yours. Where you personally sit best inside (or near) the band depends on build and muscle.
Does BMI apply to children?+
Not with these adult bands. For ages 2–19, BMI is calculated the same way but interpreted against CDC growth-chart percentiles for the child's age and sex — 'BMI-for-age' — because healthy body composition changes throughout growth. A pediatrician's chart, not an adult calculator, is the right tool for a child.
Is my BMI stored or sent anywhere?+
No. The calculation runs entirely in your browser — your height and weight are never uploaded, no account, no email, nothing tracked about the numbers you enter. It's also worth repeating the framing: this is an educational screening estimate, not medical advice; decisions about weight and health belong in a conversation with a clinician who can see the whole picture.
An educational screening estimate for adults using WHO/CDC bands — not medical advice or a diagnosis. Nothing you enter leaves your browser.