This calculator helps you determine your heart rate during exercise. Understanding your target heart rate zones is crucial for effective and safe workouts, whether you're aiming for fat burning, cardiovascular improvement, or peak performance.
years
bpm
%
.hr-rate-calculator-container {
font-family: sans-serif;
border: 1px solid #ddd;
padding: 20px;
border-radius: 8px;
max-width: 500px;
margin: 20px auto;
background-color: #f9f9f9;
}
.hr-rate-calculator-container h2 {
text-align: center;
color: #333;
margin-bottom: 15px;
}
.hr-rate-calculator-container p {
font-size: 0.9em;
color: #555;
text-align: justify;
margin-bottom: 25px;
}
.calculator-inputs {
display: grid;
grid-template-columns: 1fr;
gap: 15px;
margin-bottom: 20px;
}
.form-group {
display: flex;
align-items: center;
gap: 10px;
}
.form-group label {
flex: 1;
font-weight: bold;
color: #444;
}
.form-group input[type="number"] {
padding: 8px;
border: 1px solid #ccc;
border-radius: 4px;
width: 100px; /* Fixed width for input fields */
box-sizing: border-box; /* Include padding and border in the element's total width and height */
}
.form-group input[type="number"]:read-only {
background-color: #eee;
cursor: not-allowed;
}
.form-group .unit {
font-style: italic;
color: #777;
min-width: 40px;
}
.calculator-controls {
text-align: center;
margin-top: 20px;
display: flex;
justify-content: center;
gap: 10px;
}
.calculator-controls button {
padding: 10px 15px;
background-color: #007bff;
color: white;
border: none;
border-radius: 5px;
cursor: pointer;
font-size: 1em;
transition: background-color 0.3s ease;
}
.calculator-controls button:hover {
background-color: #0056b3;
}
.calculator-controls button:last-of-type {
background-color: #6c757d;
}
.calculator-controls button:last-of-type:hover {
background-color: #5a6268;
}
.calculator-result {
margin-top: 25px;
padding: 15px;
background-color: #e9ecef;
border: 1px solid #ced4da;
border-radius: 5px;
text-align: center;
font-size: 1.1em;
color: #333;
min-height: 50px; /* Ensure space for result */
}
function calculateMaxHeartRate(age) {
// A common formula for estimating Maximum Heart Rate (MHR) is 220 – age.
return 220 – age;
}
function calculateHeartRate() {
var ageInput = document.getElementById("age");
var intensityInput = document.getElementById("intensityPercentage");
var maxHeartRateInput = document.getElementById("maxHeartRate");
var resultDiv = document.getElementById("result");
var age = parseFloat(ageInput.value);
var intensityPercentage = parseFloat(intensityInput.value);
// Clear previous results and errors
resultDiv.innerHTML = "";
maxHeartRateInput.value = "";
// Input validation
if (isNaN(age) || age 120) {
resultDiv.innerHTML = "Please enter a valid age.";
return;
}
if (isNaN(intensityPercentage) || intensityPercentage 100) {
resultDiv.innerHTML = "Please enter an intensity level between 0 and 100.";
return;
}
// Calculate Maximum Heart Rate (MHR)
var mhr = calculateMaxHeartRate(age);
maxHeartRateInput.value = mhr.toFixed(0); // Display MHR
// Calculate Target Heart Rate (THR)
// THR = MHR * (Intensity Percentage / 100)
var targetHeartRate = mhr * (intensityPercentage / 100);
// Display the result
resultDiv.innerHTML = "For an age of " + age + " and an intensity of " + intensityPercentage + "%, your target heart rate is approximately " + targetHeartRate.toFixed(0) + " bpm.";
}
function resetCalculator() {
document.getElementById("age").value = "";
document.getElementById("intensityPercentage").value = "";
document.getElementById("maxHeartRate").value = "";
document.getElementById("result").innerHTML = "";
}