BMI Calculator
Body Mass Index — a quick way to check if your weight is in a healthy range for your height.
cm
kg
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BMI Categories
| Underweight | Less than 18.5 |
| Normal weight | 18.5 – 24.9 |
| Overweight | 25.0 – 29.9 |
| Obese | 30.0 and above |
⚠ Non-medical information. BMI is a screening tool, not a diagnostic measure. It does not account for muscle mass, bone density, age, or body composition. Consult a qualified healthcare professional for personalised health advice.
How to Use
- Choose your height unit — centimetres (cm) or feet and inches (ft/in).
- Enter your height in the selected unit.
- Choose your weight unit — kilograms (kg) or pounds (lb).
- Enter your weight in the selected unit.
- Click "Calculate BMI" to see your BMI value and weight category.
When People Use This
- Checking whether their weight falls within a healthy range for their height.
- Tracking changes over time during a fitness or weight-loss programme.
- Quick health screening before a doctor's visit or wellness check.
- Comparing personal results against standard WHO BMI categories.
Examples
Example 1
Height 175 cm, weight 70 kg → BMI = 22.9 → Normal weight (18.5–24.9).
Example 2
Height 5 ft 10 in (70 in), weight 154 lb → BMI = 22.0 → Normal weight.
Example 3
Height 160 cm, weight 90 kg → BMI = 35.2 → Obese (30+).
Example 4
Height 5 ft 4 in (64 in), weight 120 lb → BMI = 20.6 → Normal weight.
FAQ
- What is BMI?
- Body Mass Index is a number calculated from your height and weight. It is widely used as a simple screening tool for weight categories.
- Is BMI accurate for everyone?
- No. BMI does not distinguish between muscle and fat, so athletes or very muscular people may have a high BMI despite low body fat. It may also be less accurate for older adults and some ethnic groups.
- What BMI is considered healthy?
- A BMI between 18.5 and 24.9 is classified as normal weight for most adults.
- Should I use BMI to set weight-loss goals?
- BMI can be a starting point, but it is not a complete picture of health. Use it alongside other measures and professional advice.
- Why are there two unit systems?
- To make the tool easy to use no matter where you are — metric (cm/kg) is common internationally, while feet/inches and pounds are used in the US and a few other countries.