BMI Calculator
Calculate your Body Mass Index instantly. Supports metric and imperial units.
BMI Categories (WHO)
| Category | BMI Range |
|---|---|
| Underweight | < 18.5 |
| Normal weight | 18.5 – 24.9 |
| Overweight | 25.0 – 29.9 |
| Obese (Class I) | 30.0 – 34.9 |
| Obese (Class II+) | ≥ 35.0 |
How it works
Three simple steps —everything happens in your browser.
Enter Height
In cm (metric) or feet & inches (imperial).
Enter Weight
In kg (metric) or lbs (imperial).
Get Your BMI
Instant result with WHO category and visual bar.
Why choose Ercc BMI Calculator?
Metric & Imperial
Switch between kg/cm and lbs/ft+in with one click. Results update instantly.
No data leaves your browser
All calculations run locally. No health data is sent or stored anywhere.
WHO classification
See your BMI category (underweight, normal, overweight, obese) based on WHO standards.
Pro Tips
- ● BMI = weight (kg) ÷ height (m)².
- ● For imperial: BMI = 703 × weight (lbs) ÷ height (in)².
- ● BMI is a screening tool, not a diagnostic measure.
- ● It doesn’t account for muscle mass, bone density, or body composition.
- ● A “normal” BMI (18.5–24.9) doesn’t guarantee perfect health.
- ● Consult a healthcare professional for personalized advice.
Frequently Asked Questions
Body Mass Index (BMI) is a number calculated from your weight and height. It provides a simple, widely-used indicator of body fat and is used to screen for weight categories.
BMI may overestimate body fat in athletes and people with high muscle mass. It’s a screening tool, not a definitive health measure.
No. All calculations happen in your browser. No data is sent to any server, and nothing is stored.