Heart Rate Zone Calculator
Find your 5 heart rate training zones to optimize every workout.
Measure first thing in the morning.
Max Heart Rate (bpm)
Heart Rate Reserve (bpm)
Zone Guide
Zone 1 (Recovery) — Very light activity. Recovery walks, warmups.
Zone 2 (Fat Burn) — Conversational pace. Best for base fitness, fat metabolism, long runs.
Zone 3 (Aerobic) — Moderate effort. Improves cardiovascular efficiency.
Zone 4 (Threshold) — Hard effort. Improves lactate threshold and race pace.
Zone 5 (Max) — All-out sprints. Short intervals only. Improves speed and power.
Frequently Asked Questions
What is the Karvonen formula?▼
The Karvonen method uses Heart Rate Reserve (HRR = Max HR − Resting HR) to calculate training zones. It's more personalized than using Max HR alone because it accounts for your fitness level via resting heart rate.
How do I measure my resting heart rate?▼
Measure it first thing in the morning before getting out of bed. Sit or lie still for 1 minute, then count your pulse for 60 seconds. Athletes typically have lower resting heart rates (40–60 bpm) than sedentary adults (60–80 bpm).
What is max heart rate?▼
Max HR is the highest number of beats your heart can produce per minute. The formula 220 − age is a common estimate. Actual max HR can vary by ±10–20 bpm from the formula. You can test it with an all-out effort on a bike or treadmill.
Why should I train in Zone 2?▼
Zone 2 training builds your aerobic base, improves fat oxidation, and develops mitochondrial density — without the recovery cost of high-intensity training. Elite endurance athletes spend 70–80% of their training time in Zone 2.