Does BMI replace medical advice?
No. BMI is a broad screening metric and should not be treated as a diagnosis.
Health
BMI Calculator
Enter your weight in kilograms and height in centimeters to get your BMI score and see which category it falls into.
Live calculator output
Enter weight and height to get an instant BMI estimate.
How it works
BMI is calculated by dividing your weight in kilograms by the square of your height in metres: BMI = weight(kg) ÷ height(m)².
The result is compared against standard WHO categories: Underweight (below 18.5), Normal weight (18.5–24.9), Overweight (25–29.9), and Obese (30 and above). While BMI is a widely used screening tool, it does not distinguish between muscle and fat, so it should be considered alongside other measurements.
Practical example
A person who weighs 72 kg and is 178 cm (1.78 m) tall has a BMI of 72 ÷ (1.78 × 1.78) = 22.7, which falls in the Normal weight category.
A person who weighs 95 kg at the same height would have a BMI of 95 ÷ (1.78 × 1.78) = 30.0, placing them at the threshold of the Obese category.
Frequently asked questions
Does this support metric and imperial?
Yes. Use the measurement system selector to switch between kilograms/centimetres (metric) and pounds/inches (imperial).
Why might athletes get high BMI values?
BMI does not separate muscle from body fat, so muscular people can score higher.
Is BMI accurate for children?
Children and teens use age- and sex-specific BMI percentiles. This calculator is designed for adults 18 and older.
What is a healthy BMI range?
The WHO considers 18.5 to 24.9 a healthy range for most adults, but factors like muscle mass, age, and ethnicity can affect interpretation.
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