BMI BUDDY

WHO-Approved BMI Calculator - Your health, simplified.

Medical Disclaimer: This BMI calculator is for educational purposes only and is not medical advice. BMI has limitations and may not accurately reflect health for all individuals.

🔒 Privacy Policy⚕️ Always consult healthcare professionals for personalized health guidance.
WHO-Approved BMI Calculator
Calculate your Body Mass Index instantly with personalized health insights and risk assessment

Enter your height in centimeters

Enter your weight in kilograms

Must be 18 or older (adult BMI calculator)

Used for personalized health recommendations

WHO BMI Categories and Health Implications
Understanding the 6 official World Health Organization BMI categories

Underweight

BMI < 18.5

May indicate malnutrition or underlying health conditions. Increased risk of osteoporosis, compromised immune function, and potential fertility issues.

Risk Level: Moderate

Normal Weight

BMI 18.5 - 24.9

Optimal weight range for most adults. Lowest risk of weight-related health problems and associated with better overall health outcomes.

Risk Level: Low

Overweight

BMI 25.0 - 29.9

Increased risk of type 2 diabetes, cardiovascular disease, elevated blood pressure, and sleep apnea. Lifestyle changes can help reduce risks.

Risk Level: Moderate

Obese Class I

BMI 30.0 - 34.9

Significantly increased health risks including heart disease, stroke, certain cancers, and diabetes. Medical supervision recommended.

Risk Level: High

Obese Class II

BMI 35.0 - 39.9

Substantially increased health risks with high cardiovascular complications, mobility issues, and increased surgical risks.

Risk Level: Very High

Obese Class III

BMI ≥ 40.0

Extremely high health risks with life-threatening cardiovascular conditions, severe diabetes complications, and significant reduction in life expectancy.

Risk Level: Very High

Important BMI Limitations

BMI may not be accurate for:

  • Athletes with high muscle mass
  • Elderly individuals (muscle mass changes)
  • Pregnant or breastfeeding women
  • Children and adolescents under 18

Always consult healthcare professionals for:

  • Personalized health assessments
  • Weight management planning
  • Medical conditions evaluation
  • Comprehensive health guidance
Why Monitor Your BMI?

Health Benefits

  • Early detection of weight-related health risks
  • Motivation for healthy lifestyle changes
  • Tracking progress in weight management
  • Better understanding of your health status

Risk Assessment

  • Identify potential health complications
  • Guide discussions with healthcare providers
  • Plan appropriate lifestyle interventions
  • Monitor changes over time

Features

Instant Results

Get your BMI calculated in seconds with personalized insights

PDF Reports

Download beautiful, shareable health reports instantly

Privacy First

No registration, no data storage - your privacy is protected

Frequently Asked Questions

What is BMI and how is it calculated?

BMI (Body Mass Index) is a screening tool that estimates body fat based on height and weight. It's calculated using the WHO-approved formula: BMI = weight (kg) ÷ height (m)². Our calculator handles both metric and imperial units automatically.

What are the WHO BMI categories?

WHO BMI categories are: Underweight (<18.5), Normal Weight (18.5-24.9), Overweight (25-29.9), Obese Class I (30-34.9), Obese Class II (35-39.9), and Obese Class III (≥40). Each category has different health risk implications.

Is this BMI calculator medically accurate?

Yes, our calculator uses WHO-approved BMI formulas and classification standards. However, BMI is a screening tool with limitations and should not replace professional medical advice. Always consult healthcare providers for comprehensive health assessments.

How often should I check my BMI?

For general health monitoring, checking BMI monthly or quarterly is sufficient. However, if you're actively working on weight management with a healthcare provider, they may recommend more frequent monitoring as part of your personalized health plan.

When might BMI not be accurate?

BMI may be less accurate for athletes with high muscle mass, elderly individuals with muscle loss, pregnant women, and certain ethnic groups. It also doesn't distinguish between muscle and fat mass or account for body fat distribution. Consider additional metrics like waist circumference and body fat percentage.

Complete Medical Disclaimer
Medical Disclaimer

IMPORTANT: This BMI calculator is for informational and educational purposes only.

Not Medical Advice: This calculator is not intended as a substitute for professional medical advice, diagnosis, or treatment. BMI is a screening tool with limitations.

BMI Limitations: BMI does not distinguish between muscle and fat mass, and may not accurately reflect health status for:

  • Athletes and bodybuilders (high muscle mass)
  • Elderly individuals (muscle mass changes)
  • Pregnant or breastfeeding women
  • Children and adolescents under 18
  • Certain ethnic groups where different BMI ranges may apply

Consult Healthcare Professionals: Always seek the advice of your physician or other qualified health provider with any questions about your health, weight, or medical conditions.

No Doctor-Patient Relationship: Use of this calculator does not establish a doctor-patient relationship. Never disregard professional medical advice or delay seeking it based on information from this calculator.

Emergency Situations: In case of a medical emergency, call your local emergency number immediately.

Educational Tool Only
Not Medical Advice
Consult Healthcare Provider