BMI Calculator

Calculate your Body Mass Index (BMI) to understand your weight status and health risks. Simply enter your height and weight to get instant results with health recommendations.

Free online tool by QuickToolsHQ

Free BMI Calculator - Check Your Body Mass Index Online

Calculate your Body Mass Index (BMI) instantly with our free online BMI calculator. Enter your height and weight to determine if you're underweight, normal weight, overweight, or obese. Our BMI calculator uses the standard WHO formula trusted by healthcare professionals worldwide for accurate health assessments.

Medical Grade Accuracy

WHO approved BMI formula

Instant Results

Immediate BMI calculation

100% Private

No personal data stored

How to Use the BMI Calculator

1
Select your preferred unit system

Choose between metric (cm/kg) or imperial (inches/lbs) measurements

2
Enter your height and weight

Input accurate measurements for precise BMI calculation

3
Get instant BMI results

View your BMI score, weight category, and health recommendations

Understanding BMI Categories

BMI Weight Categories

UnderweightBelow 18.5
Normal weight18.5 - 24.9
Overweight25.0 - 29.9
Obese30.0 and above

BMI Calculation Formula

Metric System:

BMI = weight (kg) ÷ height² (m²)

Imperial System:

BMI = (weight (lbs) ÷ height² (inches)) × 703

Important Notes About BMI

BMI Limitations: BMI is a screening tool that doesn't account for muscle mass, bone density, age, sex, or ethnicity. Athletes and muscular individuals may have high BMI despite being healthy.

Medical Consultation: Always consult healthcare professionals for comprehensive health assessments. BMI should be used alongside other health indicators.

Age Considerations: BMI ranges may not apply to children, teenagers, pregnant women, or adults over 65. Different standards may be more appropriate.

Frequently Asked Questions About BMI

What is a healthy BMI range?

A healthy BMI is typically between 18.5 and 24.9. However, optimal BMI can vary based on individual factors like age, muscle mass, and overall health.

How accurate is BMI for health assessment?

BMI is a useful screening tool but has limitations. It doesn't distinguish between muscle and fat mass, so it may not accurately reflect health for very muscular or athletic individuals.

Should I use metric or imperial measurements?

Both systems provide equally accurate results. Choose the measurement system you're most comfortable with. Our calculator handles conversions automatically.