BMI Calculator
Calculate Body Mass Index (BMI) in Metric or Imperial units and check WHO weight category classification.
About the BMI Calculator
The CalcNest BMI Calculator provides a quick, convenient screening metric to assess whether your body weight is proportionate to your height under World Health Organization (WHO) standards.
Important Informational Disclaimer
This calculator is provided strictly for educational and informational purposes. BMI is a general screening indicator and does not constitute a clinical medical diagnosis. Please consult a qualified doctor, physician, or certified dietitian for comprehensive health assessments.
Mathematical Formula
Metric: BMI = weight(kg) / [height(m)]² | Imperial: BMI = 703 × weight(lbs) / [height(in)]² Body Mass Index (BMI) evaluates an individual’s body weight relative to their height to classify weight categories defined by the World Health Organization (WHO).
Variables & Components
Worked Example: BMI for Adult: Height 175 cm (5 ft 9 in), Weight 70 kg (154 lbs)
Evaluating the Body Mass Index and healthy weight range for an adult measuring 1.75 meters tall and weighing 70 kilograms.
Step-by-Step Calculation
- Convert height to meters: 175 cm = 1.75 m
- Square the height: 1.75 × 1.75 = 3.0625 m²
- Divide weight by height squared: 70 / 3.0625 = 22.857 kg/m²
- Round to one decimal place: BMI = 22.9
- Classification: Normal weight (WHO range: 18.5 – 24.9)
- Healthy weight range for 175 cm: 56.7 kg to 76.3 kg
How to Use This Calculator
Select either Metric (kg / cm) or Imperial (lbs / ft-in) units.
Enter your current body weight and height.
View your calculated BMI score, category badge, and estimated healthy weight range.
Read the informational guidelines and consult medical professionals for tailored clinical advice.