BMI Calculator 2025 - Free Body Mass Index Calculator
Calculate your Body Mass Index (BMI) instantly with our free online calculator. Get accurate BMI results, weight category classification, and personalized health recommendations based on World Health Organization (WHO) standards.
Understanding Body Mass Index (BMI)
What is BMI?
Body Mass Index (BMI) is a simple calculation using a person's height and weight. The BMI formula divides an adult's weight in kilograms by their height in meters squared. It's widely used as a screening tool to categorize individuals into weight categories.
BMI Formula:
BMI = weight (kg) ÷ height² (m²)
or BMI = (weight (lbs) ÷ height² (inches²)) × 703
BMI Categories
BMI Limitations
While BMI is a useful screening tool, it has limitations and doesn't directly measure body fat or overall health:
BMI may not be accurate for:
- • Athletes with high muscle mass
- • Pregnant or breastfeeding women
- • Elderly individuals with muscle loss
- • Children and adolescents
- • People with certain medical conditions
Additional factors to consider:
- • Waist circumference
- • Body fat percentage
- • Muscle mass distribution
- • Overall fitness level
- • Family history and genetics
Frequently Asked Questions
How do I calculate my BMI?
Enter your height and weight into the BMI calculator. You can use either metric units (cm, kg) or imperial units (ft/in, lbs). Your BMI will be calculated instantly.
What is a healthy BMI range?
According to WHO standards, a healthy BMI range is 18.5 to 24.9. Below 18.5 is underweight, 25-29.9 is overweight, and 30+ is considered obese.
Is BMI accurate for everyone?
BMI is a general screening tool but may not be accurate for athletes with high muscle mass, elderly individuals, or pregnant women. Consider it alongside other health metrics.