Basal Heart Rate Calculator
.bhr-calculator-container {
font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
max-width: 800px;
margin: 0 auto;
padding: 20px;
background: #f9f9f9;
border: 1px solid #e0e0e0;
border-radius: 8px;
}
.bhr-calculator-container h2 {
text-align: center;
color: #333;
margin-bottom: 20px;
}
.bhr-input-group {
margin-bottom: 15px;
}
.bhr-input-group label {
display: block;
margin-bottom: 5px;
font-weight: 600;
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.bhr-input-group input {
width: 100%;
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font-size: 16px;
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font-size: 16px;
font-weight: bold;
cursor: pointer;
margin-top: 10px;
transition: background-color 0.3s;
}
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}
.bhr-results {
margin-top: 25px;
padding: 20px;
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border: 1px solid #ddd;
border-radius: 4px;
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margin-bottom: 10px;
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.bhr-value {
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.bhr-zones-table {
width: 100%;
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margin-top: 20px;
}
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border: 1px solid #ddd;
padding: 8px;
text-align: center;
font-size: 14px;
}
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font-weight: 600;
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.bhr-zones-table tr:nth-child(even) {
background-color: #f9f9f9;
}
.bhr-zone-header {
background-color: #d32f2f;
color: white;
padding: 10px;
text-align: center;
margin-top: 20px;
border-radius: 4px 4px 0 0;
}
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margin-top: 40px;
line-height: 1.6;
color: #444;
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color: #d32f2f;
margin-top: 25px;
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.article-section p {
margin-bottom: 15px;
}
.article-section ul {
margin-bottom: 15px;
padding-left: 20px;
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.article-section li {
margin-bottom: 8px;
}
Basal Heart Rate & Training Zones Calculator
Your Age (years)
Basal (Resting) Heart Rate (bpm)
Calculate Zones
Your Cardiac Profile
Estimated Max Heart Rate:
–
Heart Rate Reserve (HRR):
–
Basal Heart Rate Status:
–
Zone
Intensity
Target Heart Rate (bpm)
Benefit
Understanding Your Basal Heart Rate
Your Basal Heart Rate (often referred to as Resting Heart Rate or RHR) is the number of times your heart beats per minute while you are at complete rest. It is a vital indicator of your overall cardiovascular fitness and heart health. The most accurate way to measure your basal heart rate is immediately after waking up in the morning, before getting out of bed.
Why It Matters
Generally, a lower basal heart rate indicates more efficient heart function and better cardiovascular fitness. For example, highly trained athletes may have a resting heart rate as low as 40 beats per minute (bpm), while the average adult typically falls between 60 and 100 bpm.
60-100 bpm: Normal range for adults.Below 60 bpm (Bradycardia): Common in athletes, but can indicate medical issues in sedentary individuals.Above 100 bpm (Tachycardia): May indicate stress, illness, or poor cardiovascular health.
The Calculation: Karvonen Method
This calculator uses the Tanaka Formula to estimate your Maximum Heart Rate (208 – 0.7 × Age) and the Karvonen Method to determine your training zones. Unlike simple percentage calculations, the Karvonen formula incorporates your specific Basal Heart Rate to determine your Heart Rate Reserve (HRR).
Formula: Target HR = ((Max HR − Resting HR) × % Intensity) + Resting HR
Training Zones Explained
Knowing your zones helps you train smarter, not just harder:
Zone 1 (Warm Up / Recovery): Very light intensity. Helps with recovery and preparing for exercise.Zone 2 (Fat Burning): Light intensity. Builds endurance and teaches the body to burn fat as fuel.Zone 3 (Aerobic): Moderate intensity. Improves blood circulation and skeletal muscle efficiency.Zone 4 (Anaerobic): Hard intensity. Increases speed endurance and lactate threshold.Zone 5 (VO2 Max): Maximum effort. Improves maximum sprint speed and neuromuscular system.
function calculateBHR() {
var age = document.getElementById('ageInput').value;
var rhr = document.getElementById('rhrInput').value;
var resultsDiv = document.getElementById('bhrResults');
var zonesBody = document.getElementById('zonesBody');
// Validation
if (!age || !rhr || isNaN(age) || isNaN(rhr)) {
alert("Please enter valid numbers for Age and Basal Heart Rate.");
return;
}
age = parseFloat(age);
rhr = parseFloat(rhr);
if (age 120) {
alert("Please enter a realistic age.");
return;
}
if (rhr 200) {
alert("Please enter a realistic heart rate (30-200 bpm).");
return;
}
// Calculations
// Using Tanaka formula for Max HR as it is generally more accurate for adults than 220-age
var maxHR = 208 – (0.7 * age);
var hrr = maxHR – rhr; // Heart Rate Reserve
// Status Assessment
var status = "";
if (rhr < 60) status = "Athletic / Excellent";
else if (rhr <= 70) status = "Good / Above Average";
else if (rhr <= 80) status = "Average";
else if (rhr <= 90) status = "Below Average";
else status = "Consult a Physician";
// Display Summary
document.getElementById('maxHRResult').innerHTML = Math.round(maxHR) + " bpm";
document.getElementById('hrrResult').innerHTML = Math.round(hrr) + " bpm";
document.getElementById('statusResult').innerHTML = status;
// Generate Zones (Karvonen)
var zones = [
{ id: 1, minPct: 0.50, maxPct: 0.60, benefit: "Recovery / Warm Up" },
{ id: 2, minPct: 0.60, maxPct: 0.70, benefit: "Fat Burning / Endurance" },
{ id: 3, minPct: 0.70, maxPct: 0.80, benefit: "Aerobic Fitness" },
{ id: 4, minPct: 0.80, maxPct: 0.90, benefit: "Anaerobic Threshold" },
{ id: 5, minPct: 0.90, maxPct: 1.00, benefit: "Maximum Performance" }
];
var tableHtml = "";
for (var i = 0; i < zones.length; i++) {
var z = zones[i];
var minBpm = Math.round((hrr * z.minPct) + rhr);
var maxBpm = Math.round((hrr * z.maxPct) + rhr);
tableHtml += "
";
tableHtml += "Zone " + z.id + " " + (z.minPct * 100) + "% – " + (z.maxPct * 100) + "% ";
tableHtml += "" + minBpm + " – " + maxBpm + " bpm ";
tableHtml += "" + z.benefit + " ";
tableHtml += " ";
}
zonesBody.innerHTML = tableHtml;
resultsDiv.style.display = "block";
}