BMI (Body Mass Index) is a quick screening number that compares your weight to your height. It is not a complete picture of health — but it is a useful first check, and it is the standard used by the World Health Organization. Enter your weight and height to see your BMI and category instantly.
BMI Calculator
Estimate only — not medical advice.
How BMI Is Calculated
BMI = weight (kg) ÷ height (m)². The standard adult categories are:
- Underweight: below 18.5
- Healthy weight: 18.5 – 24.9
- Overweight: 25 – 29.9
- Obese: 30 and above
Worked Example
A person weighing 75 kg at 1.78 m tall: BMI = 75 ÷ (1.78 × 1.78) = 75 ÷ 3.17 = 23.7 — inside the healthy range.
What BMI Does Not Tell You
BMI cannot distinguish muscle from fat. A muscular athlete can score “overweight” with low body fat, and an inactive person can score “healthy” while carrying too much fat. Use BMI together with the Body Fat Calculator and your waist measurement for a fairer picture.
Frequently Asked Questions
What is a healthy BMI?
For most adults, a BMI between 18.5 and 24.9 is considered the healthy range.
Is BMI accurate for athletes?
Often not. Muscle is denser than fat, so very muscular people can have a high BMI with a healthy body fat percentage. Check your body fat percentage as well.
Is BMI the same for men and women?
The formula and categories are the same for adult men and women. Children and teenagers use age-based percentile charts instead.
What should I do if my BMI is high?
Start with your calorie target from the TDEE Calculator and a modest deficit. If you have any medical condition, speak to a doctor before dieting.