BMI Calculator
Body Mass Index compares your weight with your height. Enter your weight in kg and height in feet/inches or centimetres.
Updated
For general information only — not medical advice. Consult a doctor or registered dietitian before making health decisions.
About this calculator
Alongside the standard WHO categories, the result shows the lower cut-offs suggested for South Asian adults, who tend to develop diabetes and heart disease at lower BMIs.
Formula
BMI = Weight (kg) ÷ Height (m)²
Height is converted to metres first. 5 ft 7 in = 67 inches = 1.70 m.
Examples
70 kg, 5 ft 7 in
BMI 24.2 — Healthy weight (WHO)
85 kg, 175 cm
BMI 27.8 — Overweight (WHO)
55 kg, 5 ft 2 in
BMI 22.2 — Healthy weight (WHO)
Reference table
| BMI | WHO category | South Asian cut-off |
|---|---|---|
| Below 18.5 | Underweight | Underweight |
| 18.5 – 22.9 | Healthy weight | Healthy weight |
| 23 – 24.9 | Healthy weight | Increased risk |
| 25 – 27.4 | Overweight | Increased risk |
| 27.5 – 29.9 | Overweight | High risk |
| 30 and above | Obese | High risk |
Important information
- BMI is a screening tool, not a diagnosis. It doesn't distinguish fat from muscle or show where fat is stored.
- Waist size is a useful extra check: for South Asians, a waist above about 90 cm (35.5 in) for men or 80 cm (31.5 in) for women suggests higher risk.
- These results are general estimates for healthy adults and are not medical advice. Children, pregnant or breastfeeding women, athletes and people with medical conditions should seek professional guidance.
Frequently asked questions
What is a healthy BMI?
18.5–24.9 by WHO standards. For South Asian adults, 18.5–22.9 is often recommended as the healthy range.
Why are cut-offs lower for South Asians?
Research shows people of South Asian origin tend to have more body fat and higher risk of type 2 diabetes and heart disease at the same BMI.
Is BMI accurate for athletes?
No — muscular people can have a high BMI without excess fat.
Can children use this calculator?
No. Children's BMI must be compared with age- and sex-specific growth charts.
How do I convert my height to metres?
Feet × 12 + inches gives total inches; multiply by 0.0254. Or select 'Feet & inches' and the calculator converts it for you.
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