Calculate Metabolic Rate Formula
function calculateBMR() {
var weight = document.getElementById("weight").value;
var height = document.getElementById("height").value;
var age = document.getElementById("age").value;
var gender = document.getElementById("gender").value;
var bmrResultDiv = document.getElementById("bmrResult");
var weightNum = parseFloat(weight);
var heightNum = parseFloat(height);
var ageNum = parseFloat(age);
if (isNaN(weightNum) || isNaN(heightNum) || isNaN(ageNum) || weightNum <= 0 || heightNum <= 0 || ageNum <= 0) {
bmrResultDiv.innerHTML = "Please enter valid positive numbers for weight, height, and age.";
return;
}
var bmr = 0;
if (gender === "male") {
// Mifflin-St Jeor Equation for Men
bmr = (10 * weightNum) + (6.25 * heightNum) – (5 * ageNum) + 5;
} else {
// Mifflin-St Jeor Equation for Women
bmr = (10 * weightNum) + (6.25 * heightNum) – (5 * ageNum) – 161;
}
bmrResultDiv.innerHTML = "Your estimated Basal Metabolic Rate (BMR) is: " + bmr.toFixed(2) + " calories/day";
}
.metabolic-calculator {
font-family: sans-serif;
max-width: 600px;
margin: 20px auto;
padding: 20px;
border: 1px solid #ddd;
border-radius: 8px;
box-shadow: 0 2px 5px rgba(0,0,0,0.1);
}
.metabolic-calculator h2 {
text-align: center;
color: #333;
margin-bottom: 15px;
}
.metabolic-calculator p {
color: #555;
line-height: 1.6;
margin-bottom: 25px;
text-align: justify;
}
.calculator-inputs {
display: grid;
grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
gap: 15px;
margin-bottom: 20px;
}
.input-group {
display: flex;
flex-direction: column;
}
.input-group label {
margin-bottom: 5px;
font-weight: bold;
color: #444;
}
.input-group input[type="number"],
.input-group select {
padding: 10px;
border: 1px solid #ccc;
border-radius: 4px;
font-size: 1rem;
}
.calculator-inputs button {
grid-column: 1 / -1; /* Span across all columns */
padding: 12px 20px;
background-color: #007bff;
color: white;
border: none;
border-radius: 4px;
font-size: 1.1rem;
cursor: pointer;
transition: background-color 0.3s ease;
}
.calculator-inputs button:hover {
background-color: #0056b3;
}
.calculator-result {
margin-top: 20px;
padding: 15px;
background-color: #e9ecef;
border: 1px solid #ced4da;
border-radius: 4px;
text-align: center;
font-size: 1.2rem;
color: #333;
}
.calculator-result strong {
color: #007bff;
}