Heart Rate Zone Calculator
Train smarter, not just harder. Enter your age and resting heart rate to find your personalized zones for fat burn, cardio, and peak performance, using the Karvonen formula.
Uses the Karvonen formula: Max HR (220 − age) and Heart Rate Reserve (Max HR − Resting HR) to calculate 5 personalized training zones.
How to Use the Heart Rate Zone Calculator
Two numbers are all you need.
Enter your age
Used to estimate your maximum heart rate with the standard 220 − age formula.
Add your resting heart rate
Check your pulse first thing in the morning before getting up, or tick "I don't know" to use the average of 70 bpm.
Review your 5 zones
Each zone shows a bpm range and its training purpose, from light warm-up to maximum effort.
How Heart Rate Zones Are Calculated
Why this method is more personalized than age alone.
📐 The Karvonen formula
Unlike a simple "220 minus age" estimate, the Karvonen formula also factors in your resting heart rate. It calculates your Heart Rate Reserve (max HR minus resting HR), then applies a percentage of that reserve on top of your resting rate — giving zones tailored to your actual fitness level.
🎯 Why zones matter
Different intensities train your body differently. Lower zones build aerobic endurance and burn a higher percentage of fat, while higher zones improve cardiovascular capacity and speed. Knowing your zones helps you train with intention instead of guessing.
Frequently Asked Questions
Common questions about heart rate training zones.
This calculator uses the Karvonen formula, which factors in your resting heart rate along with your estimated maximum heart rate (220 minus your age) to produce more personalized training zones than age alone.
The fat burn zone is typically 60-70% of your heart rate reserve. At this lighter intensity, a higher percentage of calories burned comes from fat, though total calorie burn is usually lower than at higher intensities.
Check your pulse first thing in the morning, before getting out of bed, for a full 60 seconds. The average adult resting heart rate is 60-100 beats per minute, with well-trained athletes often lower.
Zone 5 (90-100% of heart rate reserve) is very high intensity and should only be used in short bursts by people who are already fit and, ideally, cleared by a doctor for intense exercise.