BMI Calculator

Calculate your Body Mass Index instantly.




BMI Categories Chart

BMI Range Category
Below 18.5 Underweight
18.5 – 24.9 Normal weight
25 – 29.9 Overweight
30 and above Obesity

Frequently Asked Questions

BMI (Body Mass Index) is a number calculated from your weight and height. It helps determine whether you are underweight, normal weight, overweight, or obese.

Formula (Metric):
BMI = Weight (kg) ÷ Height² (m²)

Formula (Imperial):
BMI = (Weight (lb) ÷ Height² (in²)) × 703
A healthy BMI range for most adults is between 18.5 and 24.9.

BMI Categories:
Underweight: Less than 18.5
Normal weight: 18.5 – 24.9
Overweight: 25 – 29.9
Obesity: 30 or greater
BMI is a useful general guideline, but it does not measure body fat directly.

It may not be fully accurate for:
• Athletes with high muscle mass
• Older adults
• Pregnant women

For a more detailed health assessment, consult a healthcare professional.
To calculate BMI manually:

Step 1: Measure your weight and height.
Step 2: Square your height (height × height).
Step 3: Divide your weight by the squared height.

Example:
If you weigh 70 kg and your height is 1.75 m:
BMI = 70 ÷ (1.75 × 1.75)
BMI = 22.86

What Is BMI and Why It Matters?

The Body Mass Index (BMI) is a simple measurement used worldwide to assess whether a person has a healthy body weight for their height. Our free BMI calculator helps you instantly determine your BMI using either metric (kg/m) or imperial (lb/in) units.

BMI is calculated by dividing your weight by your height squared. While it does not directly measure body fat, it provides a reliable screening tool to categorize individuals as underweight, normal weight, overweight, or obese.


BMI Formula:

Metric: BMI = Weight (kg) ÷ Height² (m²)

Imperial: BMI = (Weight (lb) ÷ Height² (in²)) × 703


Maintaining a healthy BMI range can reduce the risk of heart disease, type 2 diabetes, high blood pressure, and other health conditions. However, BMI should be used as a general guideline and not as a complete diagnostic tool.

How Often Should You Check Your BMI?

Adults should check their BMI periodically, especially if they are trying to lose weight, gain muscle, or improve their overall health. Monitoring BMI over time helps track progress and maintain a healthy weight range.