BMI Calculator

Calculate your Body Mass Index

CalculatorsFreeNo Signup
4.3(496 reviews)
All Tools

Loading tool...

About BMI Calculator

A Body Mass Index (BMI) calculator that computes BMI from height and weight in both metric (kg/cm) and imperial (lbs/ft-in) units. Shows BMI category (underweight, normal, overweight, obese), healthy weight range for your height, distance from normal range boundaries, and a visual scale. Includes context about BMI limitations. Essential for health-conscious individuals and fitness tracking.

BMI Calculator Features

  • Metric & imperial
  • BMI categories
  • Healthy weight range
  • Visual scale
  • BMI limitations
Body Mass Index (BMI) is a simple screening measure calculated from height and weight: BMI = weight(kg) / height(m)². While not a direct measure of body fat, it provides a useful population-level indicator of weight categories that may lead to health problems.

How to Use

Enter your measurements:

  • Metric: Height in cm, weight in kg
  • Imperial: Height in feet/inches, weight in pounds

BMI Categories (WHO)

  • Underweight: < 18.5
  • Normal: 18.5 – 24.9
  • Overweight: 25.0 – 29.9
  • Obese I: 30.0 – 34.9
  • Obese II: 35.0 – 39.9
  • Obese III: ≥ 40.0

BMI Limitations

BMI doesn't distinguish between muscle and fat mass, doesn't account for age, sex, ethnicity, or body composition, and may misclassify muscular athletes as overweight. It's a screening tool, not a diagnostic measure.

Step-by-Step Instructions

  1. 1Select metric or imperial units.
  2. 2Enter your height.
  3. 3Enter your weight.
  4. 4View your BMI and category.
  5. 5Check your healthy weight range.

BMI Calculator — Frequently Asked Questions

What is a healthy BMI?+

The WHO defines 18.5–24.9 as 'normal weight.' However, optimal BMI varies by age, sex, and ethnicity. Asian populations may have higher health risks at lower BMI values.

Why is BMI controversial?+

BMI was created in 1832 for population statistics, not individual health. It doesn't measure body fat directly, penalizes muscular builds, and was developed using primarily European data. Body fat percentage, waist-to-hip ratio, and other metrics provide additional context.

What's the BMI formula?+

Metric: BMI = weight(kg) / height(m)². Imperial: BMI = 703 × weight(lbs) / height(in)². For example, 70kg at 175cm: BMI = 70 / 1.75² = 22.9.

More Calculators Tools

Explore all 639 other calculators tools available on Generatr

1-Sample Z-Test Calculator2-Sample Z-Test Calculator3D Surface Area CalculatorA/B Testing Significance CalculatorAbsolute Value CalculatorAbundant Number CheckerAccelerated Aging CalculatorAchromatic Number CalculatorAcyclic Chromatic Number CalculatorAdditive Persistence CalculatorAge CalculatorAging Test CalculatorAlbertson Index CalculatorAlgebraic Connectivity CalculatorAliquot Sequence CalculatorAliquot Sum CalculatorAlternating Series Test CalculatorAmicable Number FinderAnnuity CalculatorAPY CalculatorAquarium CO2 Drop CheckerArea CalculatorArea Under Curve CalculatorArithmetic Sequence CalculatorArmstrong Number CalculatorASCVD Risk CalculatorAspect Ratio CalculatorAtom Bond Connectivity CalculatorAugmented Eccentric Connectivity CalculatorAugmented Zagreb Index Calculator
View all 639 calculators tools
Share this tool: