BMI Calculator - Calculate Your Body Mass Index Online

Free BMI calculator to calculate your Body Mass Index instantly. Check your weight category (underweight, normal, overweight, obese) based on WHO standards. Works with kg/lbs and cm/ft/in units worldwide.

This free BMI calculator helps you calculate your Body Mass Index instantly. It works online, requires no signup, and supports multiple units (kg/lbs for weight, cm/ft/in for height) for users worldwide. Based on WHO (World Health Organization) standards, this tool helps you understand your weight category and health status.

Example: 70 kg or 154 lbs

Example: 175 cm or 5.7 ft

100% Free
No Signup
Works Worldwide
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BMI Categories

CategoryBMI Range
Underweight< 18.5
Normal weight18.5 – 24.9
Overweight25 – 29.9
Obesity≥ 30

How to Use

Enter your weight and height, select the units (kg/lbs for weight, cm/ft/in for height), then click Calculate to get your BMI and weight category. BMI is calculated as weight (kg) divided by height (m) squared.

Use Cases

  • Health Monitoring: Calculate BMI to monitor your body weight and health status regularly.
  • Fitness Goals: Track BMI as part of your fitness journey and weight management goals.
  • Medical Screening: Use BMI as a screening tool to assess body fat (consult healthcare professional for diagnosis).
  • General Use: Calculate BMI for personal health awareness and wellness tracking.

Accuracy Disclaimer

This BMI calculator provides results based on standard BMI formulas. BMI is a screening tool and not a diagnostic tool. Results may not be accurate for athletes with high muscle mass, pregnant women, or elderly individuals. Always consult a healthcare professional for medical advice and personalized assessment.

Frequently Asked Questions

Related Tools

Common BMI Calculations

70 kg, 175 cm

Answer: BMI = 22.9 (Normal weight)

Calculation: 70 / (1.75)² = 22.9

80 kg, 170 cm

Answer: BMI = 27.7 (Overweight)

Calculation: 80 / (1.70)² = 27.7

60 kg, 165 cm

Answer: BMI = 22.0 (Normal weight)

Calculation: 60 / (1.65)² = 22.0

55 kg, 160 cm

Answer: BMI = 21.5 (Normal weight)

Calculation: 55 / (1.60)² = 21.5

90 kg, 180 cm

Answer: BMI = 27.8 (Overweight)

Calculation: 90 / (1.80)² = 27.8

50 kg, 165 cm

Answer: BMI = 18.4 (Underweight)

Calculation: 50 / (1.65)² = 18.4

BMI Limitations

While BMI is a useful screening tool, it has limitations and may not accurately reflect body composition for everyone:

  • Athletes: High muscle mass can result in a higher BMI, even with low body fat
  • Elderly: Age-related muscle loss may affect BMI accuracy
  • Pregnant women: BMI calculations are not applicable during pregnancy
  • Children and teens: Requires age and sex-specific percentile charts
  • Body composition: BMI doesn't distinguish between muscle and fat

For a comprehensive health assessment, consider additional factors like waist circumference, body fat percentage, muscle mass, and overall fitness level. Always consult healthcare professionals for personalized medical advice.

Tips for Maintaining a Healthy BMI

Balanced Diet

Eat a variety of nutritious foods in appropriate portions

Regular Exercise

Engage in physical activity for at least 150 minutes per week

Adequate Sleep

Aim for 7-9 hours of quality sleep per night

Stay Hydrated

Drink plenty of water throughout the day

Note: These are general tips. Consult healthcare professionals for personalized health and fitness advice.

About BMI Calculator

Our free online BMI calculator helps you calculate your Body Mass Index instantly. BMI is a measure of body fat based on height and weight, commonly used as a screening tool to assess health risks associated with weight.

This BMI calculator follows WHO standards and works for users worldwide. It supports multiple units: weight in kilograms (kg) or pounds (lbs), and height in centimeters (cm), feet (ft), or inches (in). The calculator automatically converts all units to the standard metric system for accurate BMI calculation.

All calculations happen locally in your browser, ensuring complete privacy. No data is stored or transmitted. The tool is completely free to use with no registration required. Works perfectly on mobile devices, tablets, and desktops.

Important Disclaimer: BMI is a screening tool, not a diagnostic tool. It provides a general indication of weight status but does not account for individual variations in body composition, muscle mass, bone density, or other health factors. Always consult a healthcare professional for comprehensive health assessments and personalized medical advice.