BMI Calculator

Calculate your Body Mass Index and understand what it means for your health

Calculate Your BMI

BMI is a measurement of a person's weight with respect to their height. It's a screening tool that can indicate whether a person has a healthy weight.

Your BMI Result

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018.5253040+
UnderweightNormalOverweightObese

BMI Chart

Weight (kg)
Height (cm)
120
100
80
60
40
BMI 18.5
BMI 25
BMI 30
Underweight
Normal
Overweight
Obese
150
160
170
180
190
200
Find where your height and weight intersect to determine your BMI category

BMI Categories Visualization

Visual comparison of different body types based on BMI categories

Underweight

BMI < 18.5

Healthy Weight

BMI 18.5-24.9

Overweight

BMI 25-29.9

Obese

BMI ≥ 30

Understanding Body Mass Index

What BMI means and how to interpret your results

What is BMI?

Body Mass Index (BMI) is a simple calculation using a person's height and weight. The formula is BMI = kg/m² where kg is a person's weight in kilograms and m² is their height in meters squared. A BMI of 25.0 or more is overweight, while the healthy range is 18.5 to 24.9. BMI applies to most adults 18-65 years.

BMI Categories

Underweight
Less than 18.5
Higher risk of nutritional deficiency
Normal Weight
18.5 to 24.9
Lowest risk of health problems
Overweight
25 to 29.9
Increased risk of health problems
Obesity (Class 1)
30 to 34.9
High risk of health problems
Obesity (Class 2)
35 to 39.9
Very high risk of health problems
Obesity (Class 3)
40 or more
Extremely high risk of health problems

BMI Limitations

While BMI can be a useful tool for identifying potential weight issues, it has several limitations:

  • Muscle Mass: BMI doesn't distinguish between muscle and fat. Athletes may have a high BMI due to muscle mass, not excess fat.
  • Body Composition: It doesn't account for differences in bone density, muscle, or fat distribution.
  • Age and Sex: BMI may not be as accurate for older adults who have lost muscle mass or for differences between sexes.
  • Ethnicity: Different ethnic groups may have different body compositions and health risks at the same BMI.
  • Pregnancy: BMI is not applicable for pregnant women.

Health Implications

Research has shown that having a BMI in the overweight or obese range increases your risk for:

Heart Disease

Including heart attack and heart failure

Type 2 Diabetes

High blood sugar levels

Stroke

Blocked blood flow to the brain

Hypertension

High blood pressure

Certain Cancers

Including colon, breast, and kidney

Sleep Apnea

Interrupted breathing during sleep

Similarly, being underweight can lead to health problems including nutritional deficiencies, weakened immune system, and fertility issues.

Beyond BMI

While BMI is a useful screening tool, it's just one factor to consider in assessing health. Other important measures include waist circumference, blood pressure, cholesterol levels, blood sugar, and family history. For a comprehensive health assessment, consult with a healthcare professional.

Ratings

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