BMI Calculator
Check your Body Mass Index (BMI) instantly using metric or imperial units — a key indicator of your health
About BMI Calculator
A BMI Calculator (Body Mass Index Calculator) is a free online health screening tool that helps you assess your body weight relative to your height. It provides an instant calculation using WHO (World Health Organization) standards to determine if you fall into one of four categories: Underweight, Normal weight, Overweight, or Obese.
Our calculator supports both metric units (kilograms and centimeters) and imperial units (pounds, feet, and inches), making it accessible for users worldwide. All calculations happen in your browser for 100% privacy.
Key Features of BMI Calculator
Everything you need for professional bmi calculator
Instant Calculation
Get your BMI score and category immediately after entering your details. No waiting, no loading.
Metric & Imperial
Easily switch between metric (kg, cm) and imperial (lbs, ft, in) systems to suit your preference.
Health Categories
Clearly understand your result with standard WHO categories: Underweight, Normal, Overweight, and Obese.
Simple & Clean UI
A clean, responsive, and easy-to-use calculator that works perfectly on desktop, tablet, or phone.
Informative Feedback
Provides clear feedback and shows the standard BMI ranges for context, helping you interpret your score.
100% Private
All calculations happen in your browser. Your data never leaves your device, ensuring complete privacy.
How to Use BMI Calculator
Follow these simple steps to get started
Select Units
Choose between Metric (kg/cm) or Imperial (lbs/ft) units based on your preference.
Enter Your Measurements
Input your weight and height values in the selected unit system.
Get Results Instantly
Click Calculate to see your BMI score with health category classification.
Pro Tips
- Measure your height and weight at the same time of day for consistency.
- BMI is a screening tool, not a diagnostic measure. Consult a doctor for health advice.
- Athletes may have higher BMI due to muscle mass - consider other metrics too.
- Track your BMI over time to monitor health trends rather than focusing on single readings.
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Frequently Asked Questions
Everything you need to know about BMI Calculator
Body Mass Index (BMI) is a value derived from the mass (weight) and height of a person. It's a simple calculation used to give you an idea of whether you're underweight, overweight, or a healthy weight for your height.
BMI is calculated by dividing your weight in kilograms by your height in meters squared (kg/m²). For imperial units, the formula is (Weight in lbs / (Height in inches)²) × 703.
The standard categories are: Underweight (< 18.5), Normal weight (18.5–24.9), Overweight (25–29.9), and Obese (30 or greater). These help identify potential health risks.
BMI is a useful screening tool for most people, but it has limitations. It doesn't distinguish between fat and muscle mass, so athletes may have high BMI despite low body fat.
Absolutely! All calculations are performed directly in your browser. None of your personal information is ever sent to or stored on our servers.
This calculator is designed for adults (18+ years). Children need BMI-for-age percentile charts. Please consult a pediatrician for accurate BMI assessment for children.
A BMI between 18.5 and 24.9 is considered normal weight by WHO standards. However, optimal BMI can vary based on age, ethnicity, and body composition.
You should consult a healthcare provider if your BMI indicates underweight (< 18.5) or obese (≥ 30), or if you have health concerns related to your weight.
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