Calculate your personalized heart rate zones and Max HR using the Tanaka Formula.
Male
Female
Based on the Tanaka Equation: 208 – (0.7 × Age)
Zone 5 (Red) – All Out
92% – 100%
Zone 4 (Orange) – Push Pace
84% – 91%
Zone 3 (Green) – Base Pace
71% – 83%
Zone 2 (Blue) – Warm Up
61% – 70%
Zone 1 (Grey) – Very Light
< 60%
Understanding the Orangetheory Fitness Heart Rate Zones
Orangetheory Fitness (OTF) revolves around "Heart Rate Based Interval Training." By monitoring your heart rate in real-time, you can ensure you are working at the right intensity to trigger the Afterburn effect (excess post-exercise oxygen consumption, or EPOC).
What are Splat Points?
A Splat Point is earned for every minute you spend in the Orange or Red zones. The goal of every OTF class is to achieve at least 12 Splat Points. This specific threshold is believed to boost your metabolism for up to 24-36 hours after your workout is complete.
The Five Zones Breakdown
Grey Zone (Zone 1): This is your resting heart rate or very light activity. Usually 50-60% of Max HR.
Blue Zone (Zone 2): Warm-up or cool-down phase. You are moving, but not strained (61-70% of Max HR).
Green Zone (Zone 3): Your "Base Pace." This is a challenging but doable intensity you can maintain for 20-30 minutes (71-83% of Max HR).
Orange Zone (Zone 4): Your "Push Pace." This is where the magic happens. You should feel uncomfortable and out of breath (84-91% of Max HR).
Red Zone (Zone 5): "All Out" effort. This is a sprint or max-effort power move that you can only maintain for very short bursts (92-100% of Max HR).
The Tanaka Formula
Orangetheory currently utilizes the Tanaka Equation [Max HR = 208 − (0.7 × age)] as their standard baseline. While they may adjust your zones automatically after you complete 20 classes using their proprietary "Personalized Max HR" algorithm, this calculator provides the most accurate starting point used by the studio monitors.
Real-World Example
If you are a 40-year-old athlete:
Calculated Max HR: 208 – (0.7 × 40) = 180 BPM.
Your Orange Zone begins at: 180 × 0.84 = 151 BPM.
Your Red Zone begins at: 180 × 0.92 = 166 BPM.
function calculateOTF() {
var age = document.getElementById("otfAge").value;
var resultsDiv = document.getElementById("otfResults");
if (!age || age 110) {
alert("Please enter a valid age.");
return;
}
// Tanaka Formula: 208 – (0.7 * age)
var maxHR = 208 – (0.7 * age);
// Zone 1: < 61%
var z1Max = Math.round(maxHR * 0.60);
// Zone 2: 61% – 70%
var z2Min = Math.round(maxHR * 0.61);
var z2Max = Math.round(maxHR * 0.70);
// Zone 3: 71% – 83%
var z3Min = Math.round(maxHR * 0.71);
var z3Max = Math.round(maxHR * 0.83);
// Zone 4: 84% – 91%
var z4Min = Math.round(maxHR * 0.84);
var z4Max = Math.round(maxHR * 0.91);
// Zone 5: 92% – 100%
var z5Min = Math.round(maxHR * 0.92);
var z5Max = Math.round(maxHR);
// Display Results
document.getElementById("maxHRDisplay").innerHTML = "Your Estimated Max HR: " + Math.round(maxHR) + " BPM";
document.getElementById("z1Range").innerHTML = "Up to " + z1Max + " BPM";
document.getElementById("z2Range").innerHTML = z2Min + " – " + z2Max + " BPM";
document.getElementById("z3Range").innerHTML = z3Min + " – " + z3Max + " BPM";
document.getElementById("z4Range").innerHTML = z4Min + " – " + z4Max + " BPM";
document.getElementById("z5Range").innerHTML = z5Min + " – " + z5Max + " BPM";
resultsDiv.style.display = "block";
// Smooth scroll to results
resultsDiv.scrollIntoView({ behavior: 'smooth', block: 'nearest' });
}