BMI Calculator
Guide: BMI Explained: What It Means and What It Does Not
- Your BMI
- 22.9
- Category
- Normal weight
A healthy BMI (18.5 to 24.9) at your height is a weight of 56.7 kg to 76.3 kg.
BMI is a rough guide for adults. It does not measure body fat, and it can mislead for athletes, older adults and children. It is not medical advice, so talk to a doctor about your health.
Nothing you enter or choose here leaves your device. This tool runs in your browser.
How to use
- 1Choose metric (kg and cm) or imperial (pounds, feet and inches).
- 2Enter your weight and height.
- 3Read your BMI, your category and where you sit on the scale.
- 4See the weight range that is considered healthy for your height.
Frequently asked questions
How is BMI calculated?
BMI is your weight in kilograms divided by your height in metres, squared. A 70 kg person who is 1.75 m tall has a BMI of 70 / 3.0625, or about 22.9.
What do the BMI categories mean?
Under 18.5 is underweight, 18.5 to 24.9 is a normal weight, 25 to 29.9 is overweight, and 30 or more is obesity. These are the World Health Organization categories for adults.
Is BMI always accurate?
No. BMI doesn't measure body fat or where it is carried. Muscular people can have a high BMI while being healthy, and BMI can miss health risks in people with a lower muscle mass. It is a screening guide, not a diagnosis.
Can I use it for children?
No. Children's BMI is judged against growth charts for their age and sex. Ask a doctor or use a child-specific chart.
Read the guides
Learn how this works and how to get the most from it.
Money, health & time
BMI Explained: What It Means and What It Does Not
How body mass index is calculated, what the standard categories are, and why BMI is only a rough screening tool and not a diagnosis.
1 min read
Money, health & time
How Many Calories Do You Need? BMR, TDEE and Weight Goals
What BMR and TDEE mean, how daily calories are estimated, how a calorie change relates to weight change, and the limits of any calculator.
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