Health

BMI, calorie & wellness calculators

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Health · United States

BMI Calculator

Calculate BMI (weight ÷ height²) and classify it two ways — WHO (overweight ≥ 25, obese ≥ 30) and Asian/ICMR (overweight ≥ 23, obese ≥ 25, lower because Asian populations carry higher metabolic risk at a lower BMI). Plus your healthy weight range in kg for your height. A screening ratio that ignores muscle and fat distribution — not a diagnosis; pair it with the body-fat calculator. Accurate, instant and free — for United States.

kg
Weight unit

What these mean:

cm
Height unit

What these mean:

yr
Sex

What these mean:

Your BMI
22.9BMI
BMI
22.9
Healthy min (kg)
56.7
Healthy max (kg)
76.6

Your BMI is ≈ 22.9 (weight ÷ height²). WHO: normal. Asian: normal. A healthy weight for your height is about 56.7–76.6 kg (BMI 18.5–25). BMI is a screening ratio, not a diagnosis — it ignores muscle and fat distribution.

BMI

22.9

Healthy weight range

56.7–76.6 kg

WHO

Normal

Asian / ICMR

Normal

BMI ignores muscle and fat distribution

BMI is a height-to-weight ratio — it can’t tell muscle from fat or where fat sits. A lean, muscular person can read “overweight”. Pair it with a body-fat or waist measure — try the body-fat calculator.

A screening ratio, not a diagnosis

BMI is a screening ratio, not a diagnosis. It ignores muscle mass and where fat sits, and it isn’t a substitute for a clinical assessment. General guidance — not medical advice.

How we calculate this

Reviewed by Reckonist Editorial · Last reviewed July 2026. Figures follow the methods and sources set out in our editorial standards.

BMI = weight ÷ height²; WHO and Asian/ICMR category cutoffs. A screening ratio that ignores muscle and fat distribution — not a diagnosis.

WHO · ICMR/Asian cutoffs

Take it further: read your muscle-vs-fat picture with the Body Fat Calculator, track change over time with the Weight-Loss Percentage Calculator, and check your metabolic markers with the A1C Calculator.

The formula

BMI = weight ÷ height²

Body mass index is your weight in kilograms divided by your height in metres, squared. It is a quick screening ratio of weight-for-height — not a measure of body fat. Pounds and inches convert to metric first. Every value carries its unit (BMI / kg).

The equation

metric — kg and metres

BMI = weight_kg ÷ (height_m)²

Pounds × 0.453592 → kg; inches × 2.54 → cm ÷ 100 → metres. Then divide.

What it is (and isn’t)

a screening ratio

ratio, not a fat measurement

It ignores muscle and fat distribution — a screening flag, never a diagnosis.

Worked example · 70 kg, 1.75 m
Height²
3.0625 m²
BMI
≈ 22.9
Category
Normal (WHO + Asian)
  1. 1
    Square the height: 1.75 × 1.75 = 3.0625 m².
  2. 2
    Divide weight by height²: 70 ÷ 3.0625 = ≈ 22.9.
  3. 3
    Classify: 22.9 is below both the WHO (25) and Asian/ICMR (23) overweight cutoffs → Normal.
The difference that matters

WHO vs Asian/ICMR cutoffs

The standard WHO cutoffs and the Asian/ICMR cutoffs are not the same. Asian thresholds are lower — overweight starts at 23 and obese at 25— because Asian populations carry more body fat and higher metabolic risk (type-2 diabetes, heart disease) at a lower BMI. A BMI of 24 is “normal” by WHO but “overweight” by Asian/ICMR.

CategoryWHOAsian / ICMR
Underweight< 18.5< 18.5
Normal18.5 – 2518.5 – 23
Overweight25 – 3023 – 25
Obese≥ 30≥ 25

Worked example · BMI 24

A BMI of 24 sits below the WHO overweight line (25) but above the Asian/ICMR line (23). So the same number reads Normal (WHO) and Overweight (Asian/ICMR) — this tool shows both.
For your height

Your healthy weight range

A healthy BMI band is 18.5–25, so a healthy weight range for your height is 18.5 × height_m² to 25 × height_m². At 1.75 m that is about 56.7 kg to 76.6 kg. The calculator computes this range from the height you enter and shows it in kilograms.

It’s a band, not a target

A healthy weight range is a screening band, not a personal goal weight. Muscle mass, frame size and fat distribution all shift where a healthy weight actually sits for you — read it alongside a body-fat or waist measure.
Honesty

What BMI can’t see

BMI is only a ratio of weight to height. It can’t tell muscle from fat, and it can’t see where fat sits— visceral belly fat is far riskier than fat on the hips or limbs. A lean, muscular person can read “overweight” while carrying very little fat. For a fuller picture, pair BMI with a body-fat percentage or a waist measurement.

A screening ratio — not a diagnosis

BMI is a screening ratio, not a diagnosis. It ignores muscle mass and fat distribution and isn’t a substitute for a clinical assessment. General guidance — not medical advice. For muscle-vs-fat, use the body-fat calculator.
FAQ

Frequently asked questions

BMI (body mass index) is your weight in kilograms divided by your height in metres squared: BMI = weight_kg ÷ height_m². For 70 kg at 1.75 m that is 70 ÷ (1.75 × 1.75) = 70 ÷ 3.0625 ≈ 22.9. If you enter pounds and inches the tool converts them first (× 0.453592 for pounds, × 2.54 for inches). Every value carries its unit.

The WHO adult cutoffs are: underweight below 18.5, normal 18.5–25, overweight 25–30, and obese 30 or more. The Asian/ICMR cutoffs are lower: normal 18.5–23, overweight 23–25, and obese 25 or more. So a BMI of 24 is "normal" by WHO but "overweight" by Asian/ICMR. The lower Asian thresholds exist because Asian populations tend to carry more body fat and higher metabolic risk (type-2 diabetes, cardiovascular disease) at a lower BMI. This tool shows both classifications side by side.

A healthy BMI is 18.5–25, so a healthy weight range is 18.5 × height_m² to 25 × height_m². For someone 1.75 m tall that is about 56.7 kg to 76.6 kg. This tool computes your personal range from the height you enter. It is a screening band, not a target — muscle mass, frame and fat distribution all shift where a healthy weight actually sits for you.

BMI is only a height-to-weight ratio — it cannot tell muscle from fat, and it cannot see where fat is stored (visceral belly fat is far riskier than fat on the hips). A lean, muscular athlete can read "overweight" while a sedentary person with the same BMI carries much more fat. For a fuller picture, pair BMI with a body-fat percentage or a waist measurement.

No. BMI is a screening ratio, not a diagnosis. It flags whether your weight-for-height falls in a range associated with higher or lower health risk at a population level — it does not measure body fat, fitness or health directly, and it is not a substitute for a clinical assessment. Treat it as a starting point and general guidance, not medical advice.

No. The fixed adult cutoffs (WHO and Asian/ICMR) apply from about age 20. For children and teens, the same BMI number is read against age-and-sex growth percentiles instead of fixed thresholds, because healthy body composition changes rapidly with age during development.

Sources

Cutoffs & references

Methodology: BMI = weight_kg ÷ height_m². WHO cutoffs — underweight < 18.5, normal 18.5–25, overweight 25–30, obese ≥ 30. Asian/ICMR cutoffs — normal 18.5–23, overweight 23–25, obese ≥ 25. Healthy weight range = 18.5 × height_m² to 25 × height_m². All calculations run client-side and nothing is stored. A screening ratio that ignores muscle and fat distribution — general guidance, not a diagnosis or medical advice.

Cross-links

Take it further: read your muscle-vs-fat picture with the Body Fat Calculator, track change over time with the Weight-Loss Percentage Calculator, and check your metabolic markers with the A1C Calculator.

How we calculate this

Reviewed by Reckonist Editorial · Last reviewed July 2026. Figures follow the methods and sources set out in our editorial standards.

BMI = weight ÷ height²; WHO and Asian/ICMR category cutoffs, with a per-height healthy weight range. A screening ratio that ignores muscle and fat distribution — not a diagnosis. General guidance, not medical advice.

Keep going

Same-category tools follow this colour; a cross-category link keeps its own.