Calculate your body mass index (BMI) for adults, BMI Calculator

BMI Calculator

Unit System:

Weight (kg):

Height (cm):

BMI Range Graph

0 18.5 25 30 35 50

BMI Range	Category
Below 18.5	Underweight
18.5 - 24.9	Normal weight
25.0 - 29.9	Overweight
30.0 - 34.9	Obese (Class I)
35.0 and above	Severely Obese (Class II & III)

The Body Mass Index (BMI) Calculator is a tool used to estimate a person’s body fat based on their weight and height. It provides a numerical value that helps categorize individuals into different weight status categories, such as underweight, normal weight, overweight, or obese. Here’s how it works:

Formula:

BMI is calculated using the following formula:

$BMI = Height (m) ^{2} Weight (kg)$

If using pounds and inches, the formula is adjusted as follows:

$BMI = Height (in) ^{2} Weight (lbs) \times 703$

Steps to Calculate BMI:

Measure your weight in kilograms (kg) or pounds (lbs).
BMI calculator Measure your height in meters (m) or inches (in).
Plug the values into the formula and calculate.

Example:

Weight: 70 kg
Height: 1.75 m

$BMI = 1.75 ^{2} 70 = 3.062570 \approx 22.86$

BMI Categories:

Underweight: BMI < 18.5
Normal weight: BMI 18.5–24.9
Overweight: BMI 25–29.9
Obesity: BMI ≥ 30

Limitations:

BMI does not differentiate between muscle and fat, so it may not accurately reflect body composition (e.g., athletes with high muscle mass may have a high BMI but low body fat).
It does not account for factors like age, sex, bone density, or distribution of fat.

Despite its limitations, BMI is a widely used screening tool to identify potential weight-related health risks. For a more comprehensive assessment, additional metrics like waist circumference, body fat percentage, and overall health should be considered.