Heart Rate Training Zone Calculator
Calculate your personalized cardiovascular training zones using the Karvonen Formula.
Your Personalized Results
Maximum Heart Rate (Estimated): BPM
Heart Rate Reserve: BPM
| Zone | Intensity | Target Range (BPM) | Benefit |
|---|---|---|---|
| Zone 1 | 50% – 60% | Warm-up / Recovery | |
| Zone 2 | 60% – 70% | Fat Burning / Endurance | |
| Zone 3 | 70% – 80% | Aerobic / Fitness | |
| Zone 4 | 80% – 90% | Anaerobic / Performance | |
| Zone 5 | 90% – 100% | Maximum Effort / Speed |
Understanding Heart Rate Zones
Training with heart rate zones allows you to be precise with your exercise intensity. Instead of guessing how hard you are working, you can use your heart rate as a biological tachometer. This calculator utilizes the Karvonen Formula, which is widely considered more accurate than simple percentage-of-max-HR formulas because it factors in your resting heart rate (cardiovascular fitness level).
What is the Karvonen Formula?
The Karvonen formula calculates your Heart Rate Reserve (HRR) to determine your training intensity. The basic math works like this:
- Max HR: 220 – Age
- Heart Rate Reserve (HRR): Max HR – Resting HR
- Target Heart Rate: (HRR × % Intensity) + Resting HR
The Five Training Zones Explained
Zone 1: Very Light (50-60% HRR)
This zone is used for warm-ups, cool-downs, and active recovery. It improves overall health but doesn't significantly build cardiovascular endurance. It's perfect for those starting an exercise program.
Zone 2: Light / Endurance (60-70% HRR)
Often called the "fat-burning zone," Zone 2 is the foundation of endurance training. At this intensity, your body becomes more efficient at oxidizing fat and building capillary density. You should be able to hold a full conversation in this zone.
Zone 3: Moderate / Aerobic (70-80% HRR)
This is where you improve your aerobic capacity and cardiovascular strength. It makes your heart stronger and more efficient at pumping blood. Conversation becomes difficult and shorter sentences are the norm.
Zone 4: Hard / Anaerobic (80-90% HRR)
In Zone 4, you are training near your lactate threshold. Your body begins to produce lactic acid faster than it can clear it. This zone improves your ability to sustain high-speed performance and increases your "pain tolerance" for fast efforts.
Zone 5: Maximum (90-100% HRR)
This is all-out effort. It is used for interval training and high-intensity sprints. Training here improves your VO2 Max (the maximum amount of oxygen your body can use during exercise). It is sustainable only for very short bursts.
How to Measure Your Resting Heart Rate
For the most accurate results, measure your resting heart rate first thing in the morning before getting out of bed. Place two fingers on your wrist (radial pulse) or neck (carotid pulse), count the beats for 60 seconds, or count for 15 seconds and multiply by four.