Heart rate zone calculator
Find your target heart rate training zones for recovery, fat burn, aerobic, and max-effort workouts.
Your training zones
| Zone | Intensity | % Range | BPM Range |
|---|
What are heart rate zones?
Heart rate zones divide your full effort range — from resting to all-out — into bands that each train a different physiological system. Rather than guessing at "easy" or "hard" by feel alone, zones give you a number to aim for, which makes it much easier to hold yourself back on recovery days and push appropriately on hard ones.
Max HR vs. Heart Rate Reserve (Karvonen)
The simple % Max HR method sets each zone as a straight percentage of your maximum heart rate. The Karvonen method instead uses your heart rate reserve — the gap between your resting and maximum heart rate — and calculates zones as a percentage of that gap, then adds your resting rate back in. Because it accounts for your resting heart rate, Karvonen zones shift to reflect your actual fitness level: a well-trained person with a low resting heart rate gets meaningfully different (usually lower) zone numbers than the simple method would suggest.
What each zone is for
- Zone 1 — Recovery. Very light effort used for warm-ups, cool-downs, and active recovery days.
- Zone 2 — Aerobic / fat burn. Conversational-pace training that builds your aerobic base; this is where most endurance volume should live.
- Zone 3 — Moderate / tempo. Comfortably hard — sustainable for a while, but you're working.
- Zone 4 — Threshold / hard. Near your lactate threshold; sessions here are typically short intervals.
- Zone 5 — Maximum effort. All-out efforts sustainable for only seconds to a couple of minutes at a time.
Tips for training with heart rate zones
Heart rate lags behind effort by 10–30 seconds, so it's a poor guide for very short intervals — use pace or power for those instead, and save heart rate zones for steady efforts of a few minutes or more. Heat, dehydration, caffeine, and poor sleep can all push your heart rate higher at the same effort level, so don't be surprised if you drift into a higher zone on a hot day without actually working harder.
Frequently asked questions
How is max heart rate calculated?
This calculator uses the standard formula: max heart rate = 220 − age. It is a population average and can be off by 10–15 bpm for any individual, so treat the result as a starting point rather than a lab-tested value.
What is the difference between the % Max HR and Karvonen methods?
The simple method sets zones as a straight percentage of your max heart rate. The Karvonen (heart rate reserve) method also factors in your resting heart rate, which better accounts for individual fitness level and is generally considered more accurate.
Which zone should I train in?
Zone 2 (light/aerobic) builds endurance and fat-burning capacity and should make up most easy training volume. Zones 3–4 build speed and lactate threshold. Zone 5 is reserved for short, high-intensity efforts.
Can I use my fitness tracker's max heart rate estimate instead?
Yes — if your watch or chest strap has measured a genuinely maximal effort (like an all-out interval or race finish), that reading is usually more personal and accurate than the 220-minus-age formula. Use whichever number you trust more; the zone percentages apply the same way either way.
What is "Zone 2 training" and why is it popular?
Zone 2 is the low-intensity aerobic zone — roughly 60–70% of max heart rate — where your body relies heavily on fat for fuel and builds mitochondrial and cardiovascular efficiency without accumulating much fatigue. It's popular because it lets endurance athletes train a high volume of hours while still recovering well between sessions.
Does max heart rate decline with age the same way for everyone?
No. The 220-minus-age formula is a population average with a standard deviation of about 10–12 beats, so your true max could reasonably sit anywhere from 10 bpm below to 10 bpm above the estimate. Genetics, training history, and health conditions all shift the real number.
How do I find my actual resting heart rate for the Karvonen method?
Measure it first thing in the morning, before getting out of bed, ideally with a heart rate monitor or by counting your pulse for a full 60 seconds. Average it over 3–5 mornings for a more stable number than any single reading.