About this BMI Calculator
Fast • Metric & Imperial • On-device
This free BMI (Body Mass Index) Calculator supports kg/cm and lb/in.
It instantly classifies your BMI (Underweight, Normal, Overweight, Obesity) using WHO ranges
and shows a short guidance note. All calculations run locally in your browser—no signup and
no data upload.
How to use
- Select Metric (kg, cm) or Imperial (lb, in).
- Enter your weight and height, then click Calculate.
- Read your BMI value and category. Copy or Save results if you like.
BMI Ranges (WHO)
| Category | BMI |
| Underweight | < 18.5 |
| Normal | 18.5–24.9 |
| Overweight | 25–29.9 |
| Obesity | ≥ 30 |
Note: BMI is a screening tool, not a diagnosis. Body composition and other factors also matter.
FAQ
What formula does BMI use?
Metric: BMI = weight(kg) ÷ [height(m)]². Imperial: BMI = 703 × weight(lb) ÷ [height(in)]².
Are my values stored?
Input values are not uploaded anywhere. If you tap Save, results are stored only in your browser (localStorage) and you can clear them anytime.