Understanding your maximum heart rate (MHR) is a key component of designing an effective and safe exercise program. For women, while the general formulas provide a good estimate, individual factors can play a role. This calculator helps you estimate your MHR based on age, using the most common formula.
function calculateMaxHeartRate() {
var ageInput = document.getElementById("age");
var resultDiv = document.getElementById("result");
// Clear previous results
resultDiv.innerHTML = "";
// Validate input
if (ageInput.value === "" || isNaN(ageInput.value) || ageInput.value < 0) {
resultDiv.innerHTML = "Please enter a valid age.";
return;
}
var age = parseFloat(ageInput.value);
// Formula for Maximum Heart Rate (widely used, often cited for both sexes but sometimes adjusted)
// The most common and simple formula: 220 – age
// For females, sometimes the Tanaka formula (208 – 0.7 * age) is suggested for potentially better accuracy,
// but 220 – age is universally understood and a good starting point. We will use 220 – age for simplicity and common use.
var maxHeartRate = 220 – age;
// Display the result
resultDiv.innerHTML =
"Your estimated maximum heart rate is: " +
maxHeartRate.toFixed(0) +
" beats per minute (bpm).";
}
.calculator-container {
font-family: sans-serif;
border: 1px solid #ddd;
padding: 20px;
border-radius: 8px;
max-width: 500px;
margin: 20px auto;
background-color: #f9f9f9;
}
.calculator-title {
text-align: center;
color: #333;
margin-bottom: 15px;
}
.calculator-description {
font-size: 0.9em;
color: #555;
line-height: 1.5;
margin-bottom: 20px;
text-align: justify;
}
.calculator-inputs {
margin-bottom: 20px;
display: flex;
flex-direction: column;
gap: 15px;
}
.input-group {
display: flex;
flex-direction: column;
}
.input-group label {
margin-bottom: 5px;
font-weight: bold;
color: #444;
}
.input-group input[type="number"] {
padding: 10px;
border: 1px solid #ccc;
border-radius: 4px;
font-size: 1em;
width: calc(100% – 22px); /* Adjust for padding and border */
}
.calculator-button {
display: block;
width: 100%;
padding: 12px 20px;
background-color: #007bff;
color: white;
border: none;
border-radius: 4px;
font-size: 1.1em;
cursor: pointer;
transition: background-color 0.3s ease;
}
.calculator-button:hover {
background-color: #0056b3;
}
.calculator-result {
margin-top: 25px;
padding: 15px;
background-color: #e9ecef;
border-radius: 4px;
text-align: center;
font-size: 1.1em;
color: #333;
}
.calculator-result strong {
color: #007bff;
}
.error {
color: #dc3545;
font-weight: bold;
}