BMI Calculator
Calculate your Body Mass Index (BMI) quickly and accurately. Determine your weight category.
How the BMI Calculator works
Use the BMI Calculator to determine your Body Mass Index. Enter your weight in kilograms into the "Weight (kg)" field. Enter your height in centimeters into the "Height (cm)" field.
The calculator uses the formula: BMI = weight (kg) ÷ height (m)². Your height in centimeters is converted to meters for the calculation. The tool then displays your calculated BMI. It also provides a weight category based on your BMI result. This helps you understand if your weight falls within the underweight, normal, overweight, or obese range. You can adjust the input values to see how different weights and heights affect your BMI.
Formula used
BMI = weight (kg) ÷ height (m)²
| Symbol | Meaning |
|---|---|
| weight | body weight in kilograms |
| height | height in centimetres, converted to metres |
BMI is a screening number, not a diagnosis. It ignores muscle mass and body-fat distribution, so athletes often read as overweight while fit — pair it with waist measurement for a better picture.
Inputs used: Weight (kg), Height (cm).
Worked example
Here is an example of how to calculate BMI:
- Enter 70 into the "Weight (kg)" field.
- Enter 170 into the "Height (cm)" field.
- The calculator will display a BMI of 24.22 and categorize it as "Normal weight".
Result:
- BMI: 24.22
- Category: Normal weight
Frequently asked questions
- What is a BMI calculator?
- A BMI calculator computes your Body Mass Index based on your weight and height. It helps classify your weight into categories like underweight, normal, overweight, or obese.
- How is BMI calculated?
- BMI is calculated by dividing your weight in kilograms by the square of your height in meters. The formula is BMI = weight (kg) ÷ height (m)².
- What is a healthy BMI range?
- A healthy BMI range is generally considered to be between 18.5 and 24.9. Values outside this range may indicate underweight, overweight, or obesity.
- Can BMI be inaccurate for some people?
- Yes, BMI may not be accurate for athletes or very muscular individuals, as it does not distinguish between muscle and fat. It may also be less accurate for pregnant women and the elderly.
- Why is BMI important?
- BMI is a screening tool that can indicate potential weight-related health risks. It provides a general assessment of whether your weight is healthy in relation to your height.
- What formula does the BMI Calculator use?
- It uses BMI = weight (kg) ÷ height (m)², where weight is the body weight in kilograms; height is the height in centimetres, converted to metres.