How to Calculate BMI (Formula & Examples)
How to calculate Body Mass Index in metric and imperial units, with the formula, worked examples and what the number means.
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Frequently asked questions
What is the BMI formula?
BMI = weight in kilograms divided by height in metres squared. In imperial units it is 703 × weight in pounds ÷ height in inches squared.
How do I calculate BMI in pounds and inches?
Multiply your weight in pounds by 703, then divide by your height in inches squared. For 154 lb and 69 in: 703 × 154 ÷ 4761 ≈ 22.7.
Does BMI measure body fat?
No. BMI is a ratio of weight to height and does not measure body fat directly or distinguish muscle from fat. It is a screening tool, not a body‑composition test.
Is BMI the same for men and women?
The formula and adult ranges are the same for men and women. Body composition differs between individuals, which is one reason BMI is only a general guide.
How to Calculate BMI (Formula & Examples)
Body Mass Index (BMI) is a simple ratio of your weight to your height. It is widely used as a quick screening number to flag whether someone may be under or over a healthy weight for their height.
The BMI formula
Metric: BMI = weight (kg) ÷ height (m)²
Imperial: BMI = 703 × weight (lb) ÷ height (in)²
Worked examples
| Units | Inputs | Calculation | BMI |
|---|---|---|---|
| Metric | 70 kg, 1.75 m | 70 ÷ (1.75)² | 22.9 |
| Imperial | 154 lb, 69 in | 703 × 154 ÷ 69² | 22.7 |
What the number means
BMI sorts adults into broad ranges — underweight, healthy weight, overweight and obesity. It does not measure body fat directly and cannot tell muscle from fat, so it is a starting point for a conversation, not the whole picture.
This is general information, not medical advice. BMI is a screening tool, not a diagnosis — talk to a doctor about what is healthy for you.
Results are estimates for general guidance in India and may not reflect the latest local rates, fees or rules. Check official sources before making decisions.