Heart Rate Calorie Calculator App

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Heart Rate Calorie Burn Calculator

Estimate your energy expenditure based on exercise intensity and duration.

Male Female
Estimated Energy Burned: 0 kcal

How Heart Rate Relates to Calorie Burn

Using heart rate to calculate calorie expenditure is one of the most accurate ways to track exercise intensity without professional laboratory equipment. This method relies on the physiological relationship between oxygen consumption (VO2) and your heart rate. As your heart beats faster to deliver oxygen to working muscles, your metabolic rate increases, leading to a higher calorie burn.

The Math Behind the Calculation

Our calculator uses the widely recognized formulas developed by researchers (Keytel et al.), which factor in age, weight, heart rate, and gender. The formulas used are:

  • For Men: Calories = [(Age × 0.2017) + (Weight × 0.1988) + (Heart Rate × 0.6309) — 55.0969] × Time / 4.184
  • For Women: Calories = [(Age × 0.074) — (Weight × 0.1263) + (Heart Rate × 0.4472) — 20.4022] × Time / 4.184

Realistic Examples

Example 1: A 35-year-old male weighing 80kg performing a 60-minute HIIT workout with an average heart rate of 155 BPM will burn approximately 850-900 calories.

Example 2: A 28-year-old female weighing 60kg jogging for 30 minutes at a moderate pace (135 BPM) will burn roughly 240-270 calories.

Why Monitor Heart Rate Zones?

Understanding your Target Heart Rate (THR) helps you optimize your fitness goals:

  • Fat Burn Zone (50-70% Max HR): Ideal for beginners and building aerobic endurance.
  • Cardio Zone (70-85% Max HR): Enhances cardiovascular strength and burns more total calories in less time.
  • Peak Zone (85%+ Max HR): Improves anaerobic capacity and high-speed performance.
function calculateHRCalories() { var gender = document.getElementById('hr_gender').value; var age = parseFloat(document.getElementById('hr_age').value); var weight = parseFloat(document.getElementById('hr_weight').value); var hr = parseFloat(document.getElementById('hr_heartrate').value); var duration = parseFloat(document.getElementById('hr_duration').value); var resultArea = document.getElementById('hr-result-area'); var output = document.getElementById('hr_calories_output'); var zoneInfo = document.getElementById('hr_zone_info'); if (isNaN(age) || isNaN(weight) || isNaN(hr) || isNaN(duration) || age <= 0 || weight <= 0 || hr <= 0 || duration <= 0) { alert('Please enter valid positive numbers for all fields.'); return; } var calories = 0; if (gender === 'male') { // Male: [ (Age x 0.2017) + (Weight x 0.1988) + (Heart Rate x 0.6309) – 55.0969 ] x Time / 4.184 calories = ((age * 0.2017) + (weight * 0.1988) + (hr * 0.6309) – 55.0969) * duration / 4.184; } else { // Female: [ (Age x 0.074) – (Weight x 0.1263) + (Heart Rate x 0.4472) – 20.4022 ] x Time / 4.184 calories = ((age * 0.074) – (weight * 0.1263) + (hr * 0.4472) – 20.4022) * duration / 4.184; } // Catch negative results (usually happens if HR is too low for the formula's baseline) if (calories < 0) calories = 0; output.innerHTML = Math.round(calories) + " kcal"; // Calculate estimated Max HR (220 – age) to provide zone feedback var maxHR = 220 – age; var intensity = (hr / maxHR) * 100; var zoneText = ""; if (intensity = 50 && intensity = 70 && intensity < 85) { zoneText = "Intensity: Vigorous (Cardio Zone)"; } else { zoneText = "Intensity: Maximum (Anaerobic Zone)"; } zoneInfo.innerHTML = zoneText + " – " + Math.round(intensity) + "% of your Estimated Max HR"; resultArea.style.display = 'block'; }

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