How to use the bmi calculator
Compute body mass index and weight category. Enter weight, height in the fields above; the bmi, category, healthy weight range are computed instantly and plotted on the chart so you can see how the answer changes.
Formula
Variables
- w — Weight (kg)
- h — Height (cm)
Worked example
With weight = 70 kg, height = 175 cm, the calculator gives bmi ≈ 22.85714 kg/m²; category ≈ Healthy weight; healthy weight range ≈ 56.65625 – 76.25625 kg.
Frequently asked questions
What is the formula for the bmi calculation?
BMI (kg/m²) = w / (h / 100)^2. Category = [BMI]<18.5?"Underweight":([BMI]<25?"Healthy weight":([BMI]<30?"Overweight":"Obese")). Healthy weight range (kg) = 18.5 × (h / 100)^2+" – "+24.9 × (h / 100)^2. Here w is weight (kg), h is height (cm).
What inputs do I need for the bmi calculator?
You need weight in kg, height in cm. Each field is pre-filled with a typical example so you can see how the result responds as you edit the numbers.
How do I use this calculator?
Type values into the input fields. Results and the chart update instantly. Use Reset to restore the example values, Copy results to paste them elsewhere, or Share to copy a link that preserves your inputs.
Is the result exact?
Calculations use standard formulas and double-precision arithmetic, then display about seven significant figures. Real-world measurements carry uncertainty, so treat results as estimates unless your inputs are exact.