Your Estimated Maximum Heart Rate
function calculateMaxHeartRate() {
var ageInput = document.getElementById("age");
var resultDiv = document.getElementById("result");
// Clear previous results
resultDiv.innerHTML = "";
var age = parseFloat(ageInput.value);
if (isNaN(age) || age 120) {
resultDiv.innerHTML = "Please enter a valid age between 1 and 120.";
return;
}
// The most common formula for estimating Maximum Heart Rate (MHR)
var maxHeartRate = 220 – age;
resultDiv.innerHTML = "Estimated Maximum Heart Rate:
" + maxHeartRate + " bpm";
resultDiv.innerHTML += "This is an estimate based on the '220 minus age' formula.";
resultDiv.innerHTML += "Remember that individual heart rates can vary. Consult with a healthcare professional or a certified fitness trainer for personalized advice.";
}
.calculator-container {
font-family: sans-serif;
max-width: 600px;
margin: 20px auto;
padding: 20px;
border: 1px solid #e0e0e0;
border-radius: 8px;
box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}
.calculator-form h2 {
text-align: center;
color: #333;
margin-bottom: 15px;
}
.calculator-form p {
color: #555;
line-height: 1.6;
margin-bottom: 20px;
}
.form-group {
margin-bottom: 15px;
}
.form-group label {
display: block;
margin-bottom: 8px;
font-weight: bold;
color: #444;
}
.form-group input[type="number"] {
width: calc(100% – 16px);
padding: 10px;
border: 1px solid #ccc;
border-radius: 4px;
font-size: 1rem;
}
.calculator-form button {
width: 100%;
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-form button:hover {
background-color: #0056b3;
}
.calculator-result {
margin-top: 25px;
padding: 15px;
background-color: #f9f9f9;
border: 1px solid #eee;
border-radius: 4px;
text-align: center;
}
.calculator-result h3 {
color: #333;
margin-bottom: 10px;
}
#result p {
margin-bottom: 8px;
color: #444;
}
#result strong {
color: #007bff;
}