⚖️ Free Calculator

BMI Calculator

Calculate your Body Mass Index instantly using metric or imperial units. See your BMI category and healthy weight range.

UnderweightNormalOverweightObese

BMI Categories (WHO Standard)

CategoryBMI RangeHealth Risk
Underweight< 18.5Malnutrition risk
Normal weight18.5 – 24.9Minimal
Overweight25 – 29.9Moderate
Obese Class I30 – 34.9High
Obese Class II+≥ 35Very High

Frequently Asked Questions

According to the WHO, a healthy BMI is between 18.5 and 24.9. Below 18.5 is underweight, 25–29.9 is overweight, and 30 or above is considered obese.
BMI = weight (kg) ÷ height² (m²). For imperial units: BMI = 703 × weight (lbs) ÷ height² (inches²).
BMI is a general screening tool and may not be accurate for athletes (high muscle mass), elderly people, children, or pregnant women. Always consult a healthcare provider for a complete assessment.
Our calculator shows your healthy weight range based on BMI 18.5–24.9. This is a general guideline — individual healthy weight depends on many factors including age, gender, and body composition.

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⚠️ Disclaimer: BMI is a general screening indicator, not a clinical diagnosis. It does not account for muscle mass, bone density, ethnicity, age, or sex differences. Do not use these results as a substitute for professional medical advice. Consult a qualified healthcare provider for a proper health assessment.

Understanding Body Mass Index

  1. Enter your height (in cm or feet/inches) and weight (in kg or lbs).
  2. Click Calculate to see your BMI score and which category it falls into.
  3. View the healthy weight range for your height as a reference.

When You Need This

Good to Know

BMI is a useful screening tool but has real limitations. It doesn't distinguish between muscle and fat — a muscular athlete can have a "overweight" BMI while being very healthy. It also doesn't account for where fat is distributed, which matters more than total weight. Waist circumference and body fat percentage are better indicators of health risk. Always discuss BMI results with a doctor rather than self-diagnosing.