BMI calculator
Enter your weight and height to get your body mass index (BMI) and the matching category.
Free, no sign-up, nothing stored
Your BMI
22.5
Healthy weight
Healthy weight for your height: 53 to 66 kg
You are within the healthy weight range.
For people of Asian descent, health risks start to rise from a BMI of 23.
BMI calculator
How it works
The BMI is your weight in kilograms divided by the square of your height in metres. The World Health Organization uses it to describe broad categories: below 18.5, from 18.5 to 24.9, from 25 to 29.9, and 30 or more.
It is only a starting point: it does not distinguish muscle from fat, and does not suit children, pregnant women or athletes. A dietitian or a doctor can give you a real assessment.
These tools give general information. They do not replace the advice of a doctor or a qualified professional.
Go furtherNutrition & detoxFrequently asked questions
- Why are there different thresholds for Asian populations?
- At the same BMI, people of Asian descent carry on average more body fat and a higher risk of type 2 diabetes and heart disease. The WHO therefore proposed action points at 23 (increased risk) and 27.5 (high risk) in 2004. Thailand's Department of Health goes further: overweight from 23 and obesity from 25.
- Is BMI useful if I do a lot of sport?
- Less so: muscle weighs more than fat, so a muscular person can have a BMI over 25 without excess fat. Waist circumference (under 90 cm for men, 80 cm for women in Asia) is then a better marker.
- What is a healthy weight for my height?
- The range shown corresponds to a BMI of 18.5 to 24.9 (or 22.9 with the Asian thresholds). It is a broad range: where you feel well and strong inside it matters more than a single figure.
- Does BMI apply to children and older people?
- Not in the same way. For children, growth curves by age and sex are used; after 65, a slightly higher BMI (up to 27) is associated with better health, as long as muscle is preserved.
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