Calculate your Maximum Heart Rate (MHR) and Training Zones
Fox Formula (Standard: 220 – Age)
Tanaka Formula (More accurate for >40s)
Gulati Formula (Specific for Women)
Estimated Maximum Heart Rate
0 BPM
Your Training Intensity Zones
Zone
Intensity (%)
Heart Rate (BPM)
Benefit
Understanding Maximum Heart Rate (MHR)
Your Maximum Heart Rate (MHR) is the highest number of beats per minute (BPM) your heart can pump under maximum stress. It is a crucial metric for athletes and fitness enthusiasts to determine appropriate training intensities. By knowing your MHR, you can calculate specific heart rate zones to target fat loss, aerobic endurance, or peak performance.
How Is It Calculated?
While a clinical stress test is the most accurate method, several mathematical formulas provide reliable estimates based on age:
Fox Formula (220 – Age): The most common and simplest formula. It is widely used for general fitness guidelines but can overestimate MHR in younger people and underestimate it in older adults.
Tanaka Formula (208 – 0.7 × Age): Considered more accurate for healthy adults, particularly those over the age of 40. It accounts for the non-linear decline of heart rate with age.
Gulati Formula (206 – 0.88 × Age): Research suggests the standard formula often overestimates MHR for women. The Gulati formula is specifically adjusted for female physiology.
Target Heart Rate Training Zones
Once you know your MHR, you can structure your exercise based on five intensity zones:
Zone 1 (Very Light, 50-60%): Good for warm-ups, cool-downs, and active recovery.
Zone 2 (Light, 60-70%): The "Fat Burning" zone. Builds basic endurance and burns a higher percentage of calories from fat.
Zone 3 (Moderate, 70-80%): Improves aerobic fitness and blood circulation in skeletal muscles.
Zone 4 (Hard, 80-90%): Increases anaerobic tolerance and high-speed endurance. Sustainable for short periods.
Zone 5 (Maximum, 90-100%): Develops maximum performance and speed. Typically used for interval training by advanced athletes.
Important Safety Considerations
These calculations are estimates. Genetics, medication (like beta-blockers), and fitness levels can significantly alter your actual MHR. If you are starting a new exercise program, have a history of heart conditions, or experience dizziness or chest pain during exercise, consult a healthcare professional immediately.
function calculateHeartRate() {
// 1. Get inputs
var ageInput = document.getElementById('mhr-age');
var formulaSelect = document.getElementById('mhr-formula');
var age = parseFloat(ageInput.value);
var formula = formulaSelect.value;
// 2. Validation
if (isNaN(age) || age 120) {
alert("Please enter a valid age between 1 and 120.");
return;
}
// 3. Calculate MHR based on selected formula
var mhr = 0;
if (formula === 'fox') {
// Standard: 220 – Age
mhr = 220 – age;
} else if (formula === 'tanaka') {
// Tanaka: 208 – (0.7 * Age)
mhr = 208 – (0.7 * age);
} else if (formula === 'gulati') {
// Gulati (Women): 206 – (0.88 * Age)
mhr = 206 – (0.88 * age);
}
mhr = Math.round(mhr);
// 4. Calculate Zones
// Zone 1: 50-60%
var z1_min = Math.round(mhr * 0.50);
var z1_max = Math.round(mhr * 0.60);
// Zone 2: 60-70%
var z2_min = Math.round(mhr * 0.60);
var z2_max = Math.round(mhr * 0.70);
// Zone 3: 70-80%
var z3_min = Math.round(mhr * 0.70);
var z3_max = Math.round(mhr * 0.80);
// Zone 4: 80-90%
var z4_min = Math.round(mhr * 0.80);
var z4_max = Math.round(mhr * 0.90);
// Zone 5: 90-100%
var z5_min = Math.round(mhr * 0.90);
var z5_max = mhr;
// 5. Display Main Result
document.getElementById('mhr-value').innerHTML = mhr + " BPM";
document.getElementById('mhr-result').style.display = 'block';
// 6. Generate Table HTML
var tableHtml = ";
// Helper to create rows
function createRow(zone, pct, range, benefit, color) {
return '