Enter your height and weight to get your Body Mass Index, the World Health Organization category it falls in, and the weight range that would put you in the healthy band for your height. It’s a quick screening figure — an educational estimate, not a diagnosis — and it runs entirely in your browser.
Enter your weight and height.
BMI is an educational screening estimate, not a medical diagnosis. It does not distinguish muscle from fat. Consult a healthcare professional for advice about your weight.
How it works
BMI is your weight in kilograms divided by the square of your height in metres. A 70 kg person who is 175 cm tall has a BMI of about 22.9, which sits in the normal range. The tool also shows the weight range that maps to a BMI of 18.5–24.9 at your height, so you can see where the bands fall for you.
The WHO adult categories are: under 18.5 underweight, 18.5–24.9 normal, 25–29.9 overweight, and 30 or above obese. These thresholds are the same for men and women and don’t use age. BMI is a population screening tool, so it doesn’t account for muscle, build or fat distribution.
Practical examples
A normal-range result
At 175 cm and 70 kg, BMI is 22.9 — comfortably in the normal band, whose weight range for that height is roughly 56.7–76.2 kg.
Seeing the healthy range
For someone 180 cm tall, the healthy-weight band is about 59.9–80.7 kg. The range makes the single number more useful than a category label alone.
Where a muscular build misleads BMI
A 95 kg, 180 cm athlete shows a BMI of 29.3 (“overweight”), yet may carry little fat. This is exactly why BMI is a screen, not a verdict — pair it with the body fat calculator.
Frequently asked questions
Is BMI an accurate measure of health?
It’s a rough screening tool, not a diagnosis. BMI correlates with body fat across large groups but can mislead for individuals — muscular people can read as overweight, and it says nothing about where fat sits. Treat it as one signal among many and speak to a professional for a real assessment.
What are the BMI categories?
For adults, the WHO uses: below 18.5 underweight, 18.5 to 24.9 normal, 25 to 29.9 overweight, and 30 or above obese. This tool shows which band your figure falls in and the weight range for the normal band at your height.
Does BMI work the same for men and women?
The formula and adult thresholds are identical for both. Body composition differs between sexes on average, which is one reason BMI is imprecise for individuals, but the calculation itself doesn’t change.
Is BMI valid for children or older adults?
Not directly. Children and teens use age- and sex-specific percentile charts instead of fixed thresholds, and interpretation differs for the elderly. This calculator uses the standard adult formula, so results for those groups need professional context.
Why is my BMI high even though I’m fit?
Muscle is denser than fat, so a lean, muscular body can weigh enough to push BMI into the overweight range. BMI can’t tell muscle from fat. The body fat calculator gives a complementary estimate that isn’t fooled by build.
What units does it use?
Metric: weight in kilograms and height in centimetres, matching everyday use here. Enter your height as a number like 175, not in metres, and use a comma or dot for decimals in the weight.
Should I aim for the exact middle of the healthy range?
Not necessarily. The healthy band is wide on purpose, and the “best” weight within it depends on your build, muscle and health history. The range is a guide, not a target to hit precisely.
Are my height and weight kept private?
Yes. The calculation runs entirely in your browser; nothing is uploaded, and analytics never receives your measurements.
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