Determine your peak heart rate using the Tanaka, Fox, and Gulati formulas.
Calculation Results
Tanaka Formula (Recommended):— bpm
Fox Formula (Standard):— bpm
Gulati Formula (Specific for Women):— bpm
Target Training Zones (Based on Tanaka)
Zone / Intensity
Percentage
Range (BPM)
Zone 1: Very Light
50-60%
—
Zone 2: Moderate
60-70%
—
Zone 3: Aerobic
70-80%
—
Zone 4: Anaerobic
80-90%
—
Zone 5: Red Line
90-100%
—
How to Calculate Your Maximum Heart Rate Accurately
Maximum Heart Rate (MHR) is the highest number of beats per minute (bpm) your heart can safely reach during all-out physical exertion. While a clinical stress test is the gold standard, mathematical formulas provide a highly reliable estimate for training purposes.
1. The Fox Formula (220 – Age)
This is the most well-known formula. While simple, it was developed in the 1970s and can be less accurate for very young or very old individuals. It often overestimates MHR in older populations.
2. The Tanaka Formula (208 – 0.7 x Age)
Developed in 2001, the Tanaka formula is widely considered the most accurate estimation for the general adult population. It provides a more nuanced calculation that accounts for the physiological changes in the cardiovascular system as we age.
3. The Gulati Formula (206 – 0.88 x Age)
Research led by Dr. Martha Gulati found that standard formulas often overestimated MHR in women. This formula was specifically designed to provide a more precise reading for female cardiovascular health.
Why Knowing Your MHR Matters
Your MHR is the baseline for "Zone Training." By knowing your limit, you can target specific intensity levels:
Fat Burning: Usually occurs in Zones 2 and 3 (60-70% MHR).
Cardiovascular Fitness: Improved in Zone 4 (80-90% MHR).
Performance/Speed: Targeted in Zone 5 (90%+ MHR).
Example Calculation
For a 40-year-old male:
Fox: 220 – 40 = 180 bpm
Tanaka: 208 – (0.7 × 40) = 180 bpm (Note: they often align in middle age)
For a 60-year-old female:
Fox: 220 – 60 = 160 bpm
Gulati: 206 – (0.88 × 60) = 153 bpm
function calculateAccurateMHR() {
var age = document.getElementById("mhrAge").value;
var isFemale = document.getElementById("mhrFemale").checked;
if (age === "" || age <= 0) {
alert("Please enter a valid age.");
return;
}
age = parseFloat(age);
// Fox Formula
var fox = 220 – age;
// Tanaka Formula
var tanaka = 208 – (0.7 * age);
// Gulati Formula (for women)
var gulati = 206 – (0.88 * age);
// Update Results
document.getElementById("resFox").innerHTML = Math.round(fox);
document.getElementById("resTanaka").innerHTML = Math.round(tanaka);
if (isFemale) {
document.getElementById("gulatiRow").style.display = "block";
document.getElementById("resGulati").innerHTML = Math.round(gulati);
} else {
document.getElementById("gulatiRow").style.display = "none";
}
// Zone Calculations (Based on Tanaka)
var mhr = tanaka;
document.getElementById("zone1").innerHTML = Math.round(mhr * 0.50) + " – " + Math.round(mhr * 0.60);
document.getElementById("zone2").innerHTML = Math.round(mhr * 0.60) + " – " + Math.round(mhr * 0.70);
document.getElementById("zone3").innerHTML = Math.round(mhr * 0.70) + " – " + Math.round(mhr * 0.80);
document.getElementById("zone4").innerHTML = Math.round(mhr * 0.80) + " – " + Math.round(mhr * 0.90);
document.getElementById("zone5").innerHTML = Math.round(mhr * 0.90) + " – " + Math.round(mhr);
// Show result box
document.getElementById("mhr-result-box").style.display = "block";
}