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BMI Calculator

Calculate your Body Mass Index in seconds. Supports both metric (kg/cm) and imperial (lbs/in) units. See your category and healthy weight range for your height.

Your Measurements
Unit System
Weight70 kg
kg
20300
Height170 cm
cm
50250
Your Result

Fill in the details and
your result appears here.

Your BMI
Category
Healthy BMI Range18.5 – 24.9
Healthy Weight Range
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Did You Know?
BMI alone is not enough
Waist circumference is a better predictor of health risk. Men above 40 inches and women above 35 inches are at higher risk regardless of BMI.

How to use this calculator

1

Choose units

Select metric (kg/cm) or imperial (lbs/in).

2

Enter weight

Use the slider or type your weight directly.

3

Enter height

Enter height in centimetres or inches.

4

Read your BMI

See your score, category, and healthy weight range for your height.

The formula explained

BMI = Weight(kg) ÷ Height(m)²

Imperial: BMI = 703 × Weight(lbs) ÷ Height(in)²

BMI is a screening tool — not a diagnostic measure. It does not account for muscle mass, bone density, age, or ethnicity.

Frequently Asked Questions

What is a normal BMI?

18.5 to 24.9 is considered normal weight for adults according to WHO guidelines. Below 18.5 is underweight, 25–29.9 is overweight, 30+ is obese.

Is BMI accurate for athletes?

No. Muscle weighs more than fat. A muscular person may have a high BMI but very low body fat. BMI is a population-level screening tool, not individual diagnosis.

Does BMI apply to children?

For children, BMI is age and sex-specific (BMI-for-age) and interpreted using growth charts, not the adult ranges used here.

What is a healthy weight for 170cm?

Using the normal BMI range (18.5–24.9), healthy weight = 18.5 × 1.70² to 24.9 × 1.70² = 53.5 kg to 71.9 kg.

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