What is a normal BMI?

A BMI of 18.5 to 24.9 is considered normal/healthy. Under 18.5 is underweight, 25-29.9 is overweight, and 30+ is obese.

How is BMI calculated?

BMI = weight(kg) / height(m)². In imperial: BMI = (weight(lbs) / height(inches)²) × 703.

Is this BMI calculator accurate?

Yes, it uses the standard WHO formula. Note BMI doesn't account for muscle mass or body fat distribution.

Yes. All calculations happen in your browser. No data is sent to any server.

BMI Calculator - Body Mass Index Calculator

Calculate your Body Mass Index instantly. Supports metric (kg/cm) and imperial (lbs/in) units. Free, works offline.

No Upload 100% Private Free

Weight (kg)

Height (cm)

How BMI is Calculated

Enter Your Measurements

Input your weight and height in metric (kg/cm) or imperial (lbs/ft/in) units.

Instant Calculation

BMI = weight(kg) ÷ height(m)². Uses the standard WHO formula.

See Your Category

Underweight (<18.5), Normal (18.5–24.9), Overweight (25–29.9), Obese (30+).

Frequently Asked Questions

What is a healthy BMI range?

A BMI between 18.5 and 24.9 is considered normal/healthy for adults. Below 18.5 is underweight, 25–29.9 is overweight, and 30+ is obese.

Is BMI accurate for athletes?

BMI doesn't distinguish between muscle and fat. Athletes with high muscle mass may show a high BMI while being healthy. Consult a healthcare professional for a full assessment.

Is my data private?

Yes. All calculations happen locally in your browser. No data is ever sent to any server.