Understanding your target heart rate zones is crucial for effective and safe exercise. Whether you're aiming for weight loss, cardiovascular improvement, or endurance, knowing your heart rate helps you train smarter. This calculator will help you estimate your target heart rate zones based on your age and intensity level.
Moderate (50-70% of Max Heart Rate)
Vigorous (70-85% of Max Heart Rate)
function calculateTargetHeartRate() {
var ageInput = document.getElementById("age");
var intensitySelect = document.getElementById("intensity");
var resultDiv = document.getElementById("result");
var age = parseFloat(ageInput.value);
var intensity = intensitySelect.value;
// Validate age input
if (isNaN(age) || age = 120) {
resultDiv.innerHTML = "Please enter a valid age between 1 and 120.";
return;
}
// Calculate Maximum Heart Rate (MHR) using the most common formula: 220 – age
var maxHeartRate = 220 – age;
var lowerBound = 0;
var upperBound = 0;
var intensityDescription = "";
if (intensity === "moderate") {
lowerBound = maxHeartRate * 0.50;
upperBound = maxHeartRate * 0.70;
intensityDescription = "moderate intensity (50-70% of your Maximum Heart Rate)";
} else if (intensity === "vigorous") {
lowerBound = maxHeartRate * 0.70;
upperBound = maxHeartRate * 0.85;
intensityDescription = "vigorous intensity (70-85% of your Maximum Heart Rate)";
}
// Display the results
resultDiv.innerHTML =
"Your estimated Maximum Heart Rate is: " + maxHeartRate.toFixed(0) + " bpm." +
"For " + intensityDescription + ", your target heart rate zone is between " + lowerBound.toFixed(0) + " bpm and " + upperBound.toFixed(0) + " bpm.";
}