BMI Calculator

Calculate your Body Mass Index and health status

Quick answer

BMI Calculator

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.

Formula

BMI = Weight (kg) / Height² (m²)

⚖️ 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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