Heart Rate Zones Calculator
Your five training zones.
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- Private — runs in your browser
- Instant results
| Zone | Intensity | Heart rate (bpm) |
|---|
What heart-rate training zones are
Heart-rate zones divide your effort into five bands, from very light to maximum, based on a percentage of your maximum heart rate. Training in different zones produces different results — lower zones build endurance and aid recovery, while higher zones build speed and power. Knowing your zones lets you train with purpose instead of guessing.
How your zones are calculated
Your maximum heart rate is estimated with the common formula
220 − your age. The five zones are then set as percentages of that maximum:
- Zone 1 (50–60%) — very light; warm-ups, cool-downs, and recovery.
- Zone 2 (60–70%) — light; builds aerobic base and endurance, often called the "fat-burning" zone.
- Zone 3 (70–80%) — moderate; improves aerobic fitness and efficiency.
- Zone 4 (80–90%) — hard; increases speed and performance.
- Zone 5 (90–100%) — maximum; sustainable only in short bursts.
The Karvonen method
If you enter your resting heart rate, the calculator switches to the Karvonen (heart-rate reserve) method, which is more personalised. It works from your heart-rate reserve — the gap between your maximum and resting rates — so two people of the same age with different fitness levels get different zones. A fitter person with a lower resting rate gets zones tailored to them. Measure your resting heart rate first thing in the morning before getting up.
FAQ
Is "220 minus age" accurate?
It's a useful estimate but can be off by 10–15 bpm for any individual. For precise zones, a lab test or a maximal effort test under supervision gives your true maximum. The formula is fine for everyday training guidance.
Which zone should I train in?
For general health and endurance, most of your training should be in Zones 2–3, with occasional harder Zone 4–5 sessions. This "mostly easy, sometimes hard" balance is how many endurance athletes train.
Why use resting heart rate?
It reflects your fitness. Including it via the Karvonen method shifts your zones to match your cardiovascular condition, giving more meaningful targets than max-HR percentages alone.