BMI Calculator – Body Mass Index & Healthy Weight Range

Health Calculator

BMI Calculator

Calculate your Body Mass Index to assess if your weight is healthy for your height.

Your Measurements
Height
ft
in
Height
cm
Weight
lb
Your BMI Result
16 18.5 25 30 40
Healthy Weight Range
Distance to Ideal
Underweight
< 18.5
Normal
18.5 – 24.9
Overweight
25 – 29.9
Obese
≥ 30

What is BMI?

Body Mass Index (BMI) is a simple calculation using your height and weight to estimate body fat. It’s widely used as a screening tool to identify potential weight problems in adults.

BMI = Weight (kg) ÷ Height² (m²)

For example, a person who is 5’10” (178 cm) and weighs 170 lbs (77 kg) has a BMI of 24.3, which falls in the “Normal” range.

BMI Categories (WHO Standards)

The World Health Organization defines BMI categories for adults over 20 years old:

  • Underweight (BMI < 18.5): May indicate malnutrition, eating disorders, or other health issues.
  • Normal (BMI 18.5-24.9): Associated with lowest health risks for most people.
  • Overweight (BMI 25-29.9): Increased risk of heart disease, diabetes, and hypertension.
  • Obese (BMI ≥ 30): Significantly elevated health risks; may require medical intervention.

Tips for a Healthy BMI

  • Balanced diet: Focus on whole foods, lean proteins, fruits, vegetables, and whole grains.
  • Regular exercise: Aim for 150 minutes of moderate aerobic activity per week.
  • Strength training: Building muscle mass can improve body composition even without weight change.
  • Gradual changes: Losing 1-2 lbs per week is sustainable and healthier than crash diets.

BMI Limitations

  • Doesn’t measure body fat directly: Athletes with high muscle mass may have “overweight” BMI despite low body fat.
  • Age and sex differences: Women naturally have more body fat than men at the same BMI.
  • Ethnic variations: Health risks may occur at different BMI thresholds for different populations.
  • Not for children: Children and teens should use age-specific BMI percentiles instead.