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Body Mass Index (BMI) is a simple, widely-used screening measure that relates weight to height. It's not a direct measure of body fat and doesn't account for muscle mass, but it remains a standard first-pass indicator used by health organizations worldwide.
This calculator computes your BMI from your weight and height and labels it against the standard underweight/normal/overweight/obese categories.
How it works
Enter your weight in kilograms and height in centimeters. The tool divides your weight by your height in meters squared to get your BMI, then labels it against standard World Health Organization category thresholds.
- Enter weight (kg).
- Enter height (cm).
- Click Calculate to see your results.
Examples
A BMI in the normal range
A 70kg person at 175cm has a BMI of about 22.9 — within the "normal weight" range of 18.5-24.9.
Who should use it
- Getting a quick general health screening indicator.
- Tracking BMI changes over time alongside a fitness or health program.
Industry applications
- Healthcare and general wellness
- Fitness tracking
Advantages
- Quick, simple calculation requiring only weight and height.
- Uses standard, widely recognized category thresholds.
Limitations
- Doesn't distinguish muscle mass from fat mass.
- Less reliable for very muscular or very short/tall individuals.
Common mistakes to avoid
- Treating BMI as a precise health diagnosis rather than a general screening indicator.
- Not accounting for high muscle mass, which can inflate BMI without reflecting actual body fat.
Best practices
- Use BMI alongside other measures (like body fat percentage) for a fuller picture, not in isolation.
Tips
- If you're very muscular, consider checking body fat percentage as well, since BMI alone may overstate your health risk.