BMI Calculator
Enter your height and weight to calculate your BMI, weight category and a healthy weight range for your height.
Units
Your BMI
22.9
Category
Normal weight
Healthy weight range
56.7–76.3
kg
BMI is a general screening measure and doesn’t account for muscle mass, bone density, or body composition. This result is informational only and is not a medical diagnosis — consult a qualified healthcare professional for personal health guidance.
How to use the BMI Calculator
- Choose metric (cm, kg) or imperial (ft/in, lb) units.
- Enter your height and weight.
- See your BMI, weight category, and a healthy weight range for your height instantly.
What is a BMI calculator?
BMI (Body Mass Index) is a simple screening measure that relates your weight to your height. A BMI calculator does the arithmetic for you and places the result into one of four general categories: underweight, normal weight, overweight, or obese.
How the calculation works
BMI divides your weight by the square of your height, so taller people need proportionally more weight to reach the same BMI as someone shorter. The result is compared against standard weight-category ranges to show where it falls.
Formula
- Metric:
BMI = weight (kg) ÷ height (m)² - Imperial:
BMI = 703 × weight (lb) ÷ height (in)²
Worked example
A person who is 175 cm tall and weighs 70 kg has a BMI of about 22.9, which falls in the “Normal weight” category (18.5–24.9).
Understanding your result
- Underweight: BMI below 18.5
- Normal weight: BMI 18.5 to 24.9
- Overweight: BMI 25 to 29.9
- Obese: BMI 30 and above
These are general population screening categories, not a diagnosis of your individual health.
Factors that affect the result
BMI uses only height and weight, so it doesn’t distinguish muscle from fat. Athletes and very muscular people can show a higher BMI despite low body fat, while older adults can have a “normal” BMI despite reduced muscle mass. Age, sex, ethnicity and body composition can all affect how meaningful a given BMI is for an individual.
Common uses
BMI is commonly used as a quick, population-level screening tool — by individuals tracking general trends over time, and as an initial reference point that healthcare professionals may use alongside other measurements.
Important notes & limitations
This result is informational only and is not a medical diagnosis or medical advice. BMI is a general screening measure, not a direct measurement of body fat or overall health. If you have concerns about your weight or health, please consult a qualified healthcare professional.
Frequently asked questions
What is a BMI calculator used for?
It's used as a quick, general screening tool to relate your weight to your height, placing the result into a broad weight category for reference.
Is BMI an accurate measure of health?
BMI is a useful population-level screening tool, but it doesn't measure body fat directly and doesn't account for muscle mass, bone density or body composition. It's one data point, not a complete picture of health.
Is a high BMI always a health problem?
Not necessarily for every individual — muscular people, for example, can have a higher BMI without excess body fat. This is informational only; consult a healthcare professional for a proper assessment.
Does BMI apply the same way to everyone?
The standard BMI categories were developed from general adult population data and may be less precise for children, older adults, pregnant women, or very athletic individuals.
What's a healthy weight range?
The calculator shows the weight range corresponding to a "Normal weight" BMI (18.5–24.9) for your specific height.
Can I use this in pounds and inches instead of kg and cm?
Yes — switch to imperial units to enter height in feet/inches and weight in pounds.
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