BMI Calculator
Body Mass Index and category
Use this when you need a fast, accurate result — no sign-up, works entirely in your browser.
Your BMI—
Category—
How to Use
- Enter your details into the fields above.
- Click the calculate button to get your result instantly.
- Use the clear button to start a new calculation.
Example
- 175 cm, 70 kg (metric) → BMI 22.86 — Normal
- 5 ft 10 in, 160 lb (imperial) → BMI 22.96 — Normal
Formula
BMI = weight (kg) ÷ height (m)². In imperial units, BMI = 703 × weight (lb) ÷ height (in)². WHO adult categories: below 18.5 underweight, 18.5–24.9 normal, 25–29.9 overweight, 30 and above obese. BMI cannot tell muscle from fat, so heavily muscled people can read "overweight" while carrying little body fat.
About BMI Calculator
Body Mass Index and category. This free online tool gives you fast, accurate results without registration or downloads.
Everything runs locally in your browser, so your data is never uploaded or stored — privacy first.
Frequently Asked Questions
What is a healthy BMI range? +
A BMI between 18.5 and 24.9 is considered normal. Below 18.5 is underweight, 25-29.9 is overweight, and 30 or above is obese.
How is BMI calculated? +
BMI = weight (kg) ÷ height (m)². For imperial, use weight (lbs) × 703 ÷ height (inches)².
Is the BMI Calculator free to use? +
Yes, it is completely free with no registration or download required.
Is my health data private? +
Yes. All calculations happen locally in your browser. Your health information is never uploaded or stored.
Is this a substitute for medical advice? +
No. This tool provides estimates for informational purposes only and is not a substitute for professional medical advice.