BMI Calculator (Metric)

Body Mass Index Calculator (kg/cm)

BMI Calculator (Metric)

BMI for Height
cm
and Weight
kg

Body Mass Index (BMI): Complete Guide to BMI Calculation

What is Body Mass Index (BMI)?

Body Mass Index (BMI) is a medical indicator that helps assess whether a person's weight is appropriate for their height. The BMI calculator uses the formula: BMI = weight (kg) ÷ height² (m). This indicator is widely used by healthcare professionals to categorize weight status.

BMI Categories and Their Meaning

  • Underweight: BMI less than 18.5
  • Normal weight: BMI 18.5-24.9
  • Overweight: BMI 25.0-29.9
  • Obesity: BMI 30.0 and above

How to Calculate BMI Manually?

To calculate body mass index step by step:

  1. Measure your weight in kilograms
  2. Measure your height in centimeters and convert to meters
  3. Square the height value
  4. Divide weight by the obtained value

Example: With 70 kg weight and 175 cm height: BMI = 70 ÷ (1.75)² = 22.86

Limitations of BMI Calculator

It's important to remember that the BMI calculator doesn't account for:

  • Muscle mass and body composition
  • Body fat distribution
  • Age and gender
  • Ethnic background

Healthy Lifestyle and Maintaining Normal BMI

To maintain a healthy body mass index, it's recommended to:

  • Follow a balanced diet with calorie control
  • Engage in regular physical exercise (minimum 150 minutes weekly)
  • Get adequate rest (7-9 hours of sleep)
  • Manage stress and avoid harmful habits

Common BMI Examples by Height and Weight

Check the BMI for common height and weight combinations:

Note: BMI is a screening tool, not a diagnosis. Consult a healthcare professional for a personal health assessment.

Who the BMI Scale Applies To

The WHO categories on this page are for adults aged 18 and over, and they are the same for men and women: sex does not enter the BMI formula and does not move the category boundaries.

Children and teenagers aged 5–19 are read differently. Their BMI is compared with a WHO reference for age and sex and expressed as a z-score (SDS; WHO publishes the same reference as percentile charts): overweight above +1 SD, obesity above +2 SD, thinness below −2 SD and severe thinness below −3 SD. At the top of that range the two scales meet — WHO notes that +1 SD equals a BMI of 25 at 19 years, and +2 SD equals 30. WHO BMI-for-age (5–19 years)

For older adults the WHO classification above draws no separate line by age. Other guidance does, for a different purpose: the ESPEN consensus on diagnosing malnutrition counts a BMI as reduced below 20 under the age of 70 and below 22 above it. On its own that is not a diagnosis: there it only counts alongside mandatory unintentional weight loss. It is a boundary inside a diagnostic criterion, not a healthy weight range, and this page does not apply it. ESPEN Consensus Statement, Clinical Nutrition, 2015

See Also

BMI Calculator (Metric)

This calculator will help you to calculate Body Mass Index (BMI) for a given weight (kg) and height (cm). For example, it can help you find out what is BMI for 165cm and 80kg? (The answer is: 29.38). Enter height (e.g. 165 cm) and weight (e.g. 80 kg) and hit the 'Calculate' button.

FAQ

What is a healthy BMI?

A BMI between 18.5 and 24.9 is considered a normal, healthy weight for most adults. Below 18.5 is underweight, 25 to 29.9 is overweight, and 30 or above is classified as obese.

Does BMI account for muscle mass?

No. BMI is calculated only from height and weight, so it cannot tell muscle from fat. Very muscular people can have a high BMI while carrying little body fat, which is one of the formula's main limitations.

What is the BMI formula in the metric system?

BMI equals your weight in kilograms divided by your height in metres squared (BMI = kg ÷ m²). For example, 80 kg and 1.65 m give a BMI of 29.38.