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Online Calculator UK - Calculate Your BMI

BMI Formula:

\[ \text{BMI} = \frac{W}{H^2} \]

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meters

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1. What is BMI?

Definition: Body Mass Index (BMI) is a measure of body fat based on height and weight that applies to adult men and women.

Purpose: It provides a simple numeric measure of a person's thickness or thinness, allowing health professionals to discuss weight problems objectively.

2. How Does the BMI Calculator Work?

The calculator uses the formula:

\[ \text{BMI} = \frac{W}{H^2} \]

Where:

Explanation: Your weight in kilograms is divided by the square of your height in meters.

3. BMI Categories

Standard Categories:

4. Using the Calculator

Tips: Enter your weight in kilograms and height in meters. For example, 175 cm should be entered as 1.75.

5. Frequently Asked Questions (FAQ)

Q1: Is BMI accurate for everyone?
A: BMI may not be accurate for athletes (high muscle mass), pregnant women, or the elderly.

Q2: How do I convert pounds to kilograms?
A: 1 pound = 0.453592 kilograms. Multiply pounds by 0.4536 to get kg.

Q3: How do I convert feet/inches to meters?
A: 1 foot = 0.3048 meters, 1 inch = 0.0254 meters. For example, 5'7" = (5×0.3048) + (7×0.0254) = 1.7018 meters.

Q4: What's a healthy BMI range?
A: For most adults, a healthy BMI is between 18.5 and 24.9.

Q5: Should children use this calculator?
A: No, children and teens need age- and sex-specific BMI calculations.

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