BMI Calculator

Calculate your Body Mass Index and health status

⚖️ Your Measurements

📊 Your BMI

⚖️Formula

BMI = Weight (kg) / Height² (m²)

💡How it works

BMI is calculated by dividing your weight in kilograms by your height in meters squared. It helps assess if you're at a healthy weight.

What is BMI?

Body Mass Index (BMI) is a simple calculation using a person's height and weight. It is widely used to categorize individuals as underweight, normal weight, overweight, or obese. BMI is a quick screening tool for health risks related to weight.

Why does BMI matter? BMI helps identify if you are at a healthy weight for your height. It can indicate risk for conditions like heart disease, diabetes, and more.

How is BMI calculated? The formula is: BMI = Weight (kg) / Height² (m²)

BMI Categories

CategoryBMI Range
Underweight< 18.5
Normal18.5 – 24.9
Overweight25 – 29.9
Obese≥ 30

Example

If someone is 70 kg and 170 cm tall:

BMI = 70 / (1.7 × 1.7) = 24.22 (Normal)

ℹ️ What is BMI Calculator?

A BMI (Body Mass Index) calculator measures body weight relative to height. It is a widely used screening tool by healthcare professionals to categorize weight status — underweight, normal, overweight, or obese — and identify potential health risks.

📐 Formula

BMI = Weight (kg) / Height² (m²)
Weight— Body weight in kilograms (or lbs for imperial)
Height— Height in meters (or inches for imperial)
Imperial— BMI = (Weight in lbs / Height in inches²) × 703

✏️ Worked Example

Weight: 70 kg
Height: 175 cm (1.75 m)
  1. 1Convert height to meters: 175 cm = 1.75 m
  2. 2Height squared: 1.75 × 1.75 = 3.0625 m²
  3. 3BMI = 70 / 3.0625 ≈ 22.9
✅ Result: BMI = 22.9 → Normal Weight

💡 How to Interpret Results

  • ▸Below 18.5 → Underweight: may indicate malnutrition or other health concerns.
  • ▸18.5 – 24.9 → Normal/Healthy weight: associated with lowest health risk for most adults.
  • ▸25.0 – 29.9 → Overweight: increased risk of metabolic conditions.
  • ▸30.0 – 34.9 → Obese Class I | 35–39.9 → Class II | 40+ → Class III (severe): progressively higher health risks.
  • ▸BMI has limitations: it doesn't distinguish fat from muscle, doesn't account for age, sex, or ethnicity differences.

❓ Frequently Asked Questions

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