#bmi-calculator-widget label {
display: inline-block;
width: 100px;
margin-bottom: 5px;
font-weight: bold;
}
#bmi-calculator-widget input[type="number"] {
padding: 8px;
border: 1px solid #ccc;
border-radius: 4px;
width: 120px;
}
#bmi-calculator-widget select {
padding: 8px;
border: 1px solid #ccc;
border-radius: 4px;
}
#bmi-calculator-widget button {
font-size: 16px;
}
Understanding Body Mass Index (BMI)
Body Mass Index (BMI) is a simple calculation that uses your height and weight to estimate how much body fat you have. It's a common tool used to categorize individuals into different weight groups, such as underweight, normal weight, overweight, and obese. A higher BMI generally indicates a higher percentage of body fat.
BMI is calculated using the formula: weight (in kilograms) divided by height (in meters squared).
If you are using pounds and inches, the formula is: (weight (in pounds) / height (in inches squared)) x 703.
BMI Categories (WHO Standard):
- Underweight: BMI less than 18.5
- Normal weight: BMI between 18.5 and 24.9
- Overweight: BMI between 25 and 29.9
- Obese: BMI 30 or greater
It's important to remember that BMI is a screening tool and doesn't directly measure body fat. It doesn't account for factors like muscle mass, bone density, or body composition, which can influence weight. Therefore, a very muscular person might have a high BMI and be classified as overweight, even if they have very little body fat. Always consult with a healthcare professional for personalized health advice.
How to Use the Calculator:
- Enter your height, selecting the appropriate unit (meters, centimeters, feet, or inches).
- Enter your weight, selecting the appropriate unit (kilograms or pounds).
- Click the "Calculate BMI" button.
- The result will show your calculated BMI and its corresponding category.
function calculateBMI() {
var heightInput = document.getElementById("height");
var heightUnitSelect = document.getElementById("heightUnit");
var weightInput = document.getElementById("weight");
var weightUnitSelect = document.getElementById("weightUnit");
var resultDiv = document.getElementById("result");
var height = parseFloat(heightInput.value);
var heightUnit = heightUnitSelect.value;
var weight = parseFloat(weightInput.value);
var weightUnit = weightUnitSelect.value;
var bmi;
var bmiCategory;
if (isNaN(height) || isNaN(weight) || height <= 0 || weight <= 0) {
resultDiv.innerHTML = "Please enter valid positive numbers for height and weight.";
return;
}
// Convert height to meters
if (heightUnit === "cm") {
height = height / 100;
} else if (heightUnit === "feet") {
height = height * 0.3048;
} else if (heightUnit === "inches") {
height = height * 0.0254;
}
// Convert weight to kilograms
if (weightUnit === "lbs") {
weight = weight * 0.453592;
}
// Calculate BMI
bmi = weight / (height * height);
bmi = bmi.toFixed(2); // Round to 2 decimal places
// Determine BMI category
if (bmi = 18.5 && bmi = 25 && bmi <= 29.9) {
bmiCategory = "Overweight";
} else {
bmiCategory = "Obese";
}
resultDiv.innerHTML = "Your BMI is:
" + bmi + " (" + bmiCategory + ")";
}