Male
Female
Used for formula precision (Fox vs Gulati).
Auto-Select Best Formula
Fox Formula (220 – Age)
Tanaka Formula (208 – 0.7 × Age)
Gulati Formula (Women Only)
Estimated Max Heart Rate (MHR):0 BPM
Zone 1: Moderate Intensity (50-70%)
Target Range:0 – 0 BPM
Best for warm-up, weight loss, and building basic endurance.
Zone 2: Vigorous Intensity (70-85%)
Target Range:0 – 0 BPM
Best for cardiovascular fitness and high-intensity aerobic training.
Zone 3: Maximum Effort (85-100%)
Target Range:0 – 0 BPM
Warning: Short intervals only. Consult a doctor before training in this zone.
Formula used: Standard
function calculateMHR() {
var ageInput = document.getElementById('inputAge');
var age = parseFloat(ageInput.value);
var gender = document.getElementById('inputGender').value;
var formula = document.getElementById('inputFormula').value;
var resultsDiv = document.getElementById('results');
// Validation
if (isNaN(age) || age 120) {
alert("Please enter a valid age between 1 and 120.");
return;
}
var mhr = 0;
var formulaName = "";
// Logic for formula selection
if (formula === 'fox') {
mhr = 220 – age;
formulaName = "Fox Formula (Standard)";
} else if (formula === 'tanaka') {
mhr = 208 – (0.7 * age);
formulaName = "Tanaka Formula";
} else if (formula === 'gulati') {
mhr = 206 – (0.88 * age);
formulaName = "Gulati Formula";
} else {
// Auto Selection
if (gender === 'female') {
// Martha Gulati formula is widely cited for women
mhr = 206 – (0.88 * age);
formulaName = "Gulati Formula (Optimized for Women)";
} else {
// Tanaka is generally considered more accurate than Fox for adults over 40
if (age > 40) {
mhr = 208 – (0.7 * age);
formulaName = "Tanaka Formula (Optimized for Age 40+)";
} else {
mhr = 220 – age;
formulaName = "Fox Formula (Standard)";
}
}
}
// Round MHR
mhr = Math.round(mhr);
// Calculate Zones
// Zone 1: 50% – 70%
var zone1Min = Math.round(mhr * 0.50);
var zone1Max = Math.round(mhr * 0.70);
// Zone 2: 70% – 85%
var zone2Min = Math.round(mhr * 0.70);
var zone2Max = Math.round(mhr * 0.85);
// Zone 3: 85% – 100%
var zone3Min = Math.round(mhr * 0.85);
var zone3Max = mhr;
// Display Results
document.getElementById('valMHR').innerHTML = mhr;
document.getElementById('valZone1').innerHTML = zone1Min + " – " + zone1Max;
document.getElementById('valZone2').innerHTML = zone2Min + " – " + zone2Max;
document.getElementById('valZone3').innerHTML = zone3Min + " – " + zone3Max;
document.getElementById('formulaUsedName').innerHTML = formulaName;
resultsDiv.style.display = 'block';
}
Understanding the Formula for Calculating Maximum Heart Rate
Your Maximum Heart Rate (MHR) is the highest number of beats per minute (BPM) your heart can pump under maximum stress. Knowing this number is fundamental for athletes, fitness enthusiasts, and anyone looking to improve their cardiovascular health safely. It serves as the baseline for determining your personalized heart rate training zones.
Important Medical Disclaimer: The calculations provided here are estimates based on population averages. Genetic factors, medications (like beta-blockers), and fitness levels can significantly alter your true maximum heart rate. Always consult a physician before starting a vigorous exercise program.
Common Formulas Used
While the "220 minus age" rule is the most famous, exercise physiologists have developed several formulas to provide greater accuracy for different demographics.
1. The Fox Formula
This is the standard formula most people know. It is simple to calculate but can have a margin of error of up to 10-12 bpm for some individuals.
Formula: 220 – Age
Example: For a 40-year-old: 220 – 40 = 180 BPM.
2. The Tanaka Formula
Published in 2001, this formula is often considered more accurate for healthy adults, particularly those over the age of 40, as it accounts for the non-linear decline in heart rate as we age.
Formula: 208 – (0.7 × Age)
Example: For a 40-year-old: 208 – (0.7 × 40) = 180 BPM.
3. The Gulati Formula (For Women)
Research led by Martha Gulati suggested that the traditional Fox formula often overestimates the maximum heart rate for women. This formula helps correct that bias.
Formula: 206 – (0.88 × Age)
Example: For a 40-year-old woman: 206 – (0.88 × 40) = 171 BPM.
Why Do Heart Rate Zones Matter?
Once you calculate your MHR, you can use it to define specific training zones. Training in different zones yields different physiological adaptations:
Moderate Intensity (50-70% MHR): Often called the "Fat Burn" zone. It is comfortable enough to hold a conversation. It builds aerobic base and aids in recovery.
Vigorous Intensity (70-85% MHR): This is the "Cardio" zone. Breathing becomes labored. This improves your VO2 max and ability to sustain high-speed activities.
Maximum Effort (85-100% MHR): Used for HIIT (High-Intensity Interval Training). It increases speed and power but cannot be sustained for long periods.
How to Use This Calculator
Simply enter your age and select your gender. The calculator will automatically choose the most scientifically appropriate formula (Gulati for women, Fox/Tanaka for men) to give you an estimated Maximum Heart Rate. It will then break down your specific training zones so you can monitor your wearable device or smartwatch during your next workout.