BMI Calculator – Body Mass Index & Body Fat Estimate
Free BMI calculator with metric and imperial units. Check your Body Mass Index against WHO and Asian standards, see your healthy weight range, estimated body fat percentage and BMR. Instant results, no sign-up, all in your browser.
Calculate your BMI and body fat
Enter age, sex, height and weight — results update instantly.
UnderweightObese
Your BMI
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Body fat (estimate)
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BMR (basal metabolic rate)
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| Category comparison | Underweight | Normal | Overweight | Obese |
|---|---|---|---|---|
| WHO standard | < 18.5 | 18.5 – 24.9 | 25 – 29.9 | ≥ 30 |
| Chinese standard | < 18.5 | 18.5 – 23.9 | 24 – 27.9 | ≥ 28 |
Body fat is estimated with the Deurenberg formula (needs age and sex) and BMR with Mifflin-St Jeor — both are statistical estimates, not medical measurements. BMI does not distinguish muscle from fat, so athletes may read high. This tool is for reference only and is not medical advice.