Calculate Target Heart Rate Zones

Target Heart Rate Zones Calculator

Your Personalized Training Zones

Based on the Karvonen Formula, here are your target heart rate ranges:

Zone Intensity Range (BPM) Benefit
Max Heart Rate (Estimated): BPM | Heart Rate Reserve (HRR): BPM

Understanding Target Heart Rate Zones

Training with heart rate zones allows you to optimize your workouts for specific goals, whether you are trying to burn fat, improve cardiovascular endurance, or increase your top-end speed. By monitoring your heart rate, you ensure you are neither coasting too easily nor overexerting yourself to the point of injury.

The Karvonen Formula Explained

Unlike simple formulas that only use your age (like 220 minus age), this calculator uses the Karvonen Formula. This method is considered more accurate because it incorporates your Resting Heart Rate (RHR) to determine your Heart Rate Reserve (HRR).

The formula is: Target HR = ((Max HR − Resting HR) × %Intensity) + Resting HR

Breakdown of the 5 Training Zones

  • Zone 1 (50-60%): Very Light. Ideal for warm-ups, cool-downs, and active recovery. It improves overall health but won't significantly boost fitness.
  • Zone 2 (60-70%): Light (The Fat Burn Zone). This is the "base" training zone. It builds aerobic endurance and trains your body to become efficient at burning fat as a fuel source.
  • Zone 3 (70-80%): Moderate (Aerobic). This improves blood circulation and strengthens your heart and skeletal muscles. It's the sweet spot for improving cardiovascular fitness.
  • Zone 4 (80-90%): Hard (Anaerobic). You are training your body to handle lactic acid. This zone increases speed and high-intensity endurance. It feels heavy and breathing is labored.
  • Zone 5 (90-100%): Maximum. This is "all-out" effort. It should only be used for very short bursts of interval training. It improves peak performance and reaction time.

Example Calculation

Suppose you are 30 years old with a Resting Heart Rate of 60 BPM:

  1. Estimated Max Heart Rate: 220 – 30 = 190 BPM.
  2. Heart Rate Reserve (HRR): 190 – 60 = 130 BPM.
  3. For Zone 2 (60%): (130 * 0.60) + 60 = 138 BPM.
  4. Your target range for Zone 2 would start at 138 beats per minute.
function calculateHRZones() { var age = parseFloat(document.getElementById("userAge").value); var rhr = parseFloat(document.getElementById("restingHR").value); var resultsDiv = document.getElementById("hrResults"); var tableBody = document.getElementById("zoneTableBody"); var maxHRDisplay = document.getElementById("maxHRVal"); var hrrDisplay = document.getElementById("hrrVal"); if (isNaN(age) || age 120) { alert("Please enter a valid age between 1 and 120."); return; } if (isNaN(rhr) || rhr 150) { alert("Please enter a valid resting heart rate (typically between 30 and 150)."); return; } var maxHR = 220 – age; var hrr = maxHR – rhr; if (hrr <= 0) { alert("Resting heart rate cannot be higher than maximum heart rate. Please check your inputs."); return; } maxHRDisplay.innerText = maxHR; hrrDisplay.innerText = hrr; var zones = [ { name: "Zone 1", intensity: "50-60%", low: 0.50, high: 0.60, benefit: "Warm-up / Recovery", color: "#e0e0e0" }, { name: "Zone 2", intensity: "60-70%", low: 0.60, high: 0.70, benefit: "Fat Burn / Endurance", color: "#d1f2eb" }, { name: "Zone 3", intensity: "70-80%", low: 0.70, high: 0.80, benefit: "Aerobic Fitness", color: "#fcf3cf" }, { name: "Zone 4", intensity: "80-90%", low: 0.80, high: 0.90, benefit: "Speed / Anaerobic", color: "#f5cba7" }, { name: "Zone 5", intensity: "90-100%", low: 0.90, high: 1.00, benefit: "Maximum Effort", color: "#f1948a" } ]; var html = ""; for (var i = 0; i < zones.length; i++) { var lowBPM = Math.round((hrr * zones[i].low) + rhr); var highBPM = Math.round((hrr * zones[i].high) + rhr); html += ""; html += "" + zones[i].name + ""; html += "" + zones[i].intensity + ""; html += "" + lowBPM + " – " + highBPM + " BPM"; html += "" + zones[i].benefit + ""; html += ""; } tableBody.innerHTML = html; resultsDiv.style.display = "block"; resultsDiv.scrollIntoView({ behavior: 'smooth' }); }

Leave a Comment