Heart Rate Calculator
Understanding your heart rate is crucial for monitoring your cardiovascular health and fitness levels. This calculator helps you estimate your target heart rate zones during exercise.
Your Age (years):
Activity Level:
Low (e.g., sitting, light walking)
Moderate (e.g., brisk walking, light jogging)
High (e.g., running, intense sports)
Calculate Target Heart Rate
Your Target Heart Rate Zone:
function calculateHeartRate() {
var ageInput = document.getElementById("age");
var activityLevelSelect = document.getElementById("activityLevel");
var resultDiv = document.getElementById("targetHeartRateZone");
var age = parseFloat(ageInput.value);
var activityLevel = parseFloat(activityLevelSelect.value);
if (isNaN(age) || age <= 0) {
resultDiv.innerHTML = "Please enter a valid age.";
return;
}
// Karvonen Formula for Target Heart Rate Zone
// MHR = 220 – Age (Maximum Heart Rate)
// THR = ((MHR – RHR) * % Intensity) + RHR
// For simplicity in this calculator, we'll use a simplified estimation assuming a resting heart rate (RHR) of 70 bpm.
// A more precise calculation would require the user's RHR.
var maxHeartRate = 220 – age;
var restingHeartRate = 70; // Assumed resting heart rate for simplified calculation
var lowerBound = Math.round(((maxHeartRate – restingHeartRate) * activityLevel) + restingHeartRate);
var upperBound = Math.round(((maxHeartRate – restingHeartRate) * (activityLevel + 0.2)) + restingHeartRate); // Using +0.2 for a typical zone range
if (lowerBound < 0) lowerBound = 0;
if (upperBound < 0) upperBound = 0;
resultDiv.innerHTML = lowerBound + " – " + upperBound + " beats per minute (bpm)";
}
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font-family: sans-serif;
max-width: 500px;
margin: 20px auto;
padding: 20px;
border: 1px solid #ccc;
border-radius: 8px;
box-shadow: 0 2px 5px rgba(0,0,0,0.1);
}
.calculator-title {
text-align: center;
color: #333;
margin-bottom: 15px;
}
.calculator-description {
text-align: justify;
color: #555;
margin-bottom: 20px;
line-height: 1.6;
}
.calculator-input-section {
margin-bottom: 20px;
}
.calculator-input-section label {
display: block;
margin-bottom: 8px;
font-weight: bold;
color: #444;
}
.calculator-input-section input[type="number"],
.calculator-input-section select {
width: calc(100% – 20px);
padding: 10px;
margin-bottom: 15px;
border: 1px solid #ddd;
border-radius: 4px;
box-sizing: border-box; /* Include padding and border in the element's total width and height */
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button {
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width: 100%;
padding: 12px 15px;
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color: white;
border: none;
border-radius: 4px;
font-size: 16px;
cursor: pointer;
transition: background-color 0.3s ease;
margin-bottom: 20px;
}
button:hover {
background-color: #0056b3;
}
.calculator-result-section {
text-align: center;
margin-top: 20px;
padding: 15px;
background-color: #e9ecef;
border: 1px solid #ced4da;
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}
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margin: 5px 0;
font-size: 1.1em;
color: #333;
}
.calculator-result-section p:first-child {
font-weight: bold;
color: #007bff;
}