BMI Calculator
Enter your height and weight to calculate BMI, weight category, and a healthy weight range. Supports both metric and imperial units.
Body information
Result
What Is BMI?
BMI (Body Mass Index) is calculated by dividing body weight by height squared. It is widely used as a simple screening indicator for body weight status.
Formula: BMI = weight (kg) ÷ height (m)$^2$
Korean guidance often classifies BMI 23 and above as overweight, which is slightly stricter than some Western standards.
BMI Classification
- Below 18.5: Underweight
- 18.5 to 22.9: Normal
- 23.0 to 24.9: Overweight
- 25.0 to 29.9: Obese I
- 30.0 and above: Obese II
Example
Example: height 170 cm, weight 68 kg
- BMI: 68 ÷ (1.70)$^2$ = 23.5 → Overweight
- Healthy range: 53.4 to 71.9 kg
Frequently Asked Questions
Does a high BMI always mean poor health?
No. BMI is only a screening metric, and people with high muscle mass may have a high BMI without excess body fat.
Does this standard apply to children and teens?
No. Children and teenagers use age- and sex-specific BMI percentiles. This calculator is for adults.
What target weight should I use to improve BMI?
The calculator shows a healthy weight range based on BMI 18.5 to 22.9. Sustainable habits matter more than rapid weight change.