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What is my BMI?

Calculate your Body Mass Index (BMI) and understand what it means for your health. Get personalized interpretation of your results.

What This Calculator Is

A BMI (Body Mass Index) calculator determines your weight-to-height ratio, a common screening tool for weight categories. While BMI has limitations—it doesn't account for muscle mass, bone density, or fat distribution—it provides a quick starting point for discussions about healthy weight ranges and potential health risks.

Who This Calculator Is For

Anyone curious about their weight category, people starting a health or fitness journey who want baseline measurements, and healthcare providers conducting initial screenings. It's a starting point for health conversations, not a diagnostic tool.

When to Use This Calculator

Use this calculator as an initial health screening, when beginning a weight management program, during regular health check-ins, or when your doctor references BMI during appointments. Always combine BMI with other health metrics for a complete picture.

Calculate Your BMI

feet (ft)
inches (in)
pounds (lbs)

Your Results

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Body Mass Index
Enter your height and weight to calculate

BMI Visual Scale

1518.5253040
Underweight
Healthy Weight
Overweight
Obesity
CategoryBMI Range
Underweight		Below 18.5
Healthy Weight		18.5 to 24.9
Overweight		25.0 to 29.9
Obesity		30.0 or greater

The results above are guidelines for typical situations. Please consult with a doctor for your macronutrient needs if you are an athlete, training for a specific purpose, or on a special diet due to a disease, pregnancy, or other conditions.

How BMI Is Calculated

BMI = weight (kg) / height (m)². For pounds and inches: BMI = (weight × 703) / height². The result categorizes you as underweight, normal, overweight, or obese based on standard ranges.

BMI = weight(kg) / height(m)^2
Healthy weight range (lbs) computed from BMI 18.5 to 24.9 applied to the person's height
Where:
weight in lbs (US) converted via *0.453592, or kg directly (metric)
height from feet+inches converted to meters via *0.0254 per inch, or cm/100 (metric)
Categories: BMI<18.5 Underweight; 18.5-24.9 Healthy Weight; 25-29.9 Overweight; >=30 Obesity
Assumptions:
Standard BMI formula (weight/height^2), no age/sex adjustment despite age being collected
Defaults: US units, 5'10", 170 lbs if inputs missing
BMI rounded to 1 decimal; healthy weight range rounded to nearest integer (lbs) or 1 decimal (kg)

Key Takeaways

  • •BMI doesn't distinguish between muscle and fat — athletes may have 'high' BMI but low body fat
  • •BMI categories: <18.5 underweight, 18.5-24.9 normal, 25-29.9 overweight, 30+ obese
  • •Waist circumference and body fat percentage provide additional context
  • •BMI is less accurate for older adults who have lost muscle mass
  • •Focus on overall health habits rather than just the BMI number

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