Heart Rate Zones Calculator
Heart rate zones are ranges of heartbeats per minute that correspond to different exercise intensities. Training in specific zones helps you optimize your workouts — whether your goal is fat burning, endurance building, or peak performance. Understanding your zones lets you train smarter, not just harder.
Heart rate zones are typically divided into five levels based on your maximum heart rate (MHR). Zone 1 (50–60% MHR) is light recovery, Zone 2 (60–70%) builds aerobic base and burns fat, Zone 3 (70–80%) improves aerobic fitness, Zone 4 (80–90%) increases speed and lactate threshold, and Zone 5 (90–100%) develops maximum performance. Your maximum heart rate is commonly estimated as 220 minus your age, though individual variation exists.
How it works
Maximum Heart Rate (MHR) = 220 − age. Zone boundaries are calculated as percentages of MHR: Zone 1 = 50–60%, Zone 2 = 60–70%, Zone 3 = 70–80%, Zone 4 = 80–90%, Zone 5 = 90–100%.
Use cases
- Optimizing cardio workouts for specific fitness goals
- Training for endurance events like marathons or cycling races
- Maximizing fat burning during exercise sessions
- Monitoring exercise intensity to prevent overtraining
Frequently asked questions
How do I calculate my maximum heart rate?
The most common estimate is 220 minus your age. For example, a 40-year-old would have an estimated maximum heart rate of 180 beats per minute. This is a population average, so your true maximum may be somewhat higher or lower — a supervised stress test gives a more precise value.
What heart rate zone is best for burning fat?
Zone 2, at 60–70% of your maximum heart rate, is often called the fat-burning zone because a larger share of the calories burned comes from fat. However, higher-intensity zones burn more total calories per minute, so the best zone also depends on how long you can sustain the effort.
Is the 220 minus age formula accurate for everyone?
It is a reasonable estimate for most people, but individual variation can be significant — real maximum heart rates commonly differ by 10 or more beats per minute from the formula. Fitness level, genetics, and medications can all shift your actual maximum. Treat the calculated zones as a starting point and adjust based on how workouts feel.
Which zone should I train in to improve endurance?
Most endurance training happens in Zones 2 and 3 (60–80% of maximum heart rate), which build your aerobic base and improve cardiovascular fitness. Many training plans recommend spending the majority of weekly volume in Zone 2, with smaller doses of Zone 4 work to raise your lactate threshold.
How long can I safely stay in Zone 5?
Zone 5 (90–100% of maximum heart rate) is an all-out effort that most people can only sustain for short intervals, typically from a few seconds up to a few minutes. It is normally used in structured interval sessions with recovery periods in between. If you are new to exercise or have health concerns, consult a doctor before high-intensity training.