LAZYFIX

BMI Calculator

Body mass index and category from height & weight

Height (cm)

Weight (kg)

Enter your height and weight

Underweight< 18.5
Normal18.5 – 24.9
Overweight25.0 – 29.9
Obese≥ 30.0
BMI

Understand your body mass index

BMI (body mass index) is your weight in kilograms divided by the square of your height in meters — a quick gauge of whether your weight is appropriate for your height. This calculator uses the standard WHO ranges to show underweight, normal, overweight, and obese categories plus your healthy weight range. Everything runs in your browser.

Instant category

See underweight, normal, overweight, and obese categories with a color gauge.

Healthy weight range

Shows the healthy weight range for your height in kg or lb.

Metric & imperial

Enter cm and kg, or feet, inches, and pounds.

FAQ

Frequently asked questions

How is BMI calculated?

BMI = weight (kg) ÷ height (m) squared. For 170 cm and 65 kg, that is 65 ÷ (1.7 × 1.7) ≈ 22.5.

What is a normal BMI range?

By WHO standards, 18.5–24.9 is normal. Below 18.5 is underweight, 25 or above is overweight, and 30 or above is obese.

Can BMI alone judge my health?

BMI is a rough indicator. It does not account for muscle mass, body fat, age, or sex, so athletes may see skewed results. Consult a professional for an accurate assessment.

Is my height and weight stored?

No. All calculation happens in your browser; your inputs are never sent or stored anywhere.