BMI Calculator
BMI divides your weight in kilograms by the square of your height in meters. A BMI of 18.5–24.9 is healthy for most adul...
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How It Works
BMI divides your weight in kilograms by the square of your height in meters. A BMI of 18.5–24.9 is healthy for most adults. BMI is a screening tool — it does not measure body fat directly.
Quick Reference
Underweight
BMI < 18.5
< 18.5
Normal weight
BMI 18.5–24.9
18.5–24.9
Overweight
BMI 25–29.9
25–29.9
Obese
BMI ≥ 30
≥ 30
Tips & Shortcuts
BMI does not distinguish between muscle and fat. Athletes may have high BMI but low body fat.
Check waist circumference alongside BMI for a more complete health picture.
BMI thresholds differ by ethnicity — Asian populations use lower cutoffs (23 overweight, 27.5 obese).
Use BMI as a starting point, not a final health diagnosis.
Common Mistakes
Using pounds and inches without converting
Use kg and cm. 1 kg = 2.205 lbs, 1 inch = 2.54 cm.
Judging health by BMI alone
BMI is a screening tool. A doctor considers muscle mass, age, and other factors.
Frequently Asked Questions
A BMI between 18.5 and 24.9 is considered healthy for most adults. Below 18.5 is underweight, 25–29.9 is overweight, and 30 or above is obese.
BMI can overestimate body fat in athletes because muscle weighs more than fat. Body fat percentage testing is more accurate for muscular individuals.
The BMI formula is identical for both sexes, but women naturally carry more body fat at the same BMI value. The healthy category (18.5–24.9) applies to both.
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