Estimate your Maximum Heart Rate (MHR) and training zones.
Male
Female
Fox Formula (Standard: 220 – Age)
Tanaka Formula (More accurate for >40)
Gulati Formula (Specific for Women)
Haskell & Fox (Aggressive)
Estimated Maximum Heart Rate
0BPM
Your Target Heart Rate Training Zones
Zone
Intensity
Target Range (BPM)
Benefit
function calculateMHR() {
var ageInput = document.getElementById("inputAge");
var genderInput = document.getElementById("inputGender");
var formulaInput = document.getElementById("inputFormula");
var resultsDiv = document.getElementById("resultsArea");
var age = parseFloat(ageInput.value);
var gender = genderInput.value;
var formula = formulaInput.value;
if (isNaN(age) || age 120) {
alert("Please enter a valid age between 1 and 120.");
resultsDiv.style.display = "none";
return;
}
var mhr = 0;
var formulaName = "";
// Calculation Logic
if (formula === "fox") {
// Fox Formula: 220 – Age
mhr = 220 – age;
formulaName = "Fox Formula (220 – Age)";
} else if (formula === "tanaka") {
// Tanaka Formula: 208 – (0.7 * Age)
mhr = 208 – (0.7 * age);
formulaName = "Tanaka Formula (208 – 0.7 × Age)";
} else if (formula === "gulati") {
// Gulati Formula: 206 – (0.88 * Age) (Best for women)
// If user is male but selects Gulati, we can still run it but it's intended for women.
mhr = 206 – (0.88 * age);
formulaName = "Gulati Formula (206 – 0.88 × Age)";
} else if (formula === "haskell") {
// Haskell: 220 – Age (Often conflated with Fox, effectively the same in most simple calculators,
// but sometimes cited as 220 – age for adults. Let's use a variation or standard.)
// Let's use the Inbar Formula for variety if they want aggressive: 205.8 – (0.685 * age)
// Or stick to 220-age as standard Haskell. Let's stick to simple logic.
mhr = 220 – age;
formulaName = "Standard Formula";
}
// Round MHR to nearest whole number
mhr = Math.round(mhr);
// Update UI
document.getElementById("displayMHR").innerText = mhr;
document.getElementById("formulaUsedText").innerText = "Based on: " + formulaName;
// Calculate Zones
// Zone 1: 50-60%
// Zone 2: 60-70%
// Zone 3: 70-80%
// Zone 4: 80-90%
// Zone 5: 90-100%
var z1_min = Math.round(mhr * 0.50);
var z1_max = Math.round(mhr * 0.60);
var z2_min = Math.round(mhr * 0.60);
var z2_max = Math.round(mhr * 0.70);
var z3_min = Math.round(mhr * 0.70);
var z3_max = Math.round(mhr * 0.80);
var z4_min = Math.round(mhr * 0.80);
var z4_max = Math.round(mhr * 0.90);
var z5_min = Math.round(mhr * 0.90);
var z5_max = mhr;
var tableHtml = "";
tableHtml += '
Calculating your Maximum Heart Rate (MHR) is the cornerstone of designing an effective and safe cardiovascular training program. Whether you are an elite athlete aiming for peak performance or a beginner looking to improve heart health, knowing your MHR helps you define specific heart rate zones to target during exercise.
What is Maximum Heart Rate?
Maximum Heart Rate is the highest number of beats per minute (BPM) your heart can achieve during maximum physical exertion. It is largely determined by genetics and age. Contrary to popular belief, MHR does not significantly indicate fitness levels; a higher MHR doesn't necessarily mean you are more fit, nor does it automatically decline just because your fitness improves. However, MHR naturally decreases as we age.
Formulas Used in This Calculator
There isn't one single "perfect" formula for everyone, which is why our calculator offers multiple options based on scientific research:
1. The Fox Formula (220 – Age)
This is the most widely known and simplest formula. While easy to remember, it has a standard deviation of about 10-12 beats per minute, meaning it can sometimes underestimate MHR for older adults or overestimate it for younger individuals.
Example: For a 40-year-old: 220 – 40 = 180 BPM.
2. The Tanaka Formula (208 – 0.7 × Age)
Published in 2001, this formula is often considered more accurate for healthy adults over the age of 40. It accounts for the non-linear decline of heart rate as we age.
Example: For a 40-year-old: 208 – (0.7 × 40) = 180 BPM.
3. The Gulati Formula (206 – 0.88 × Age)
Research led by Martha Gulati suggested that the traditional "220 minus age" formula often overestimates MHR for women. This specific formula provides a more accurate baseline for female physiology.
Target Heart Rate Zones Explained
Once you know your MHR, you can calculate your training zones. Training in different zones yields different physiological benefits:
Zone 1 (50-60%): Warm Up / Recovery. Used for warming up before a workout or active recovery days. It promotes blood flow and helps muscles recover.
Zone 2 (60-70%): Fat Burning / Endurance. This is the "conversational pace" zone. It teaches your body to utilize fat as fuel and builds your aerobic base.
Zone 3 (70-80%): Aerobic Capacity. Training here improves blood circulation and the efficiency of your heart and lungs. You will breathe harder and break a sweat.
Zone 4 (80-90%): Anaerobic Threshold. You can only sustain this effort for short periods. This zone increases your lactate threshold and performance speed.
Zone 5 (90-100%): Maximum Effort. Used for very short intervals (sprinting). Consult a doctor before training in this zone, as it places maximum stress on the cardiovascular system.
How to Use These Results
To use these numbers effectively, consider wearing a heart rate monitor (chest strap or wrist-based tracker) during your workouts. Aim to keep your heart rate within the specific range that aligns with your fitness goals for that session.
For example, if your goal is weight loss, spending the majority of your time in Zone 2 is often recommended. If you are training for a 5K race, you might incorporate interval training in Zone 4.
Medical Disclaimer: The results provided by this calculator are estimates based on population averages. Individual heart rates can vary significantly due to genetics, medication, and health conditions. Always consult with a physician before starting a new exercise program, especially if you have a history of heart conditions or high blood pressure.