Target Heart Rate Zone Calculator
Find your training heart rate zones based on age, and optionally resting heart rate.
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Heart rate training zones divide exercise intensity into ranges, each associated with a different training effect — from easy recovery effort to maximum exertion — based on percentages of your maximum heart rate.
The simplest estimate for max heart rate is 220 minus your age: a 30-year-old has an estimated max heart rate of 190 bpm. This is a population-average formula, not a measured value, so it can be off by 10-15 bpm or more for any given individual — a real max heart rate test (typically supervised, involving maximal exertion) is more accurate but impractical for most people to obtain.
If you provide a resting heart rate, the calculator switches to the Karvonen formula, which is more personalized: it first computes your heart rate reserve (max heart rate minus resting heart rate), then calculates each zone as a percentage of that reserve, added back to your resting rate — rather than a percentage of max heart rate alone. This accounts for individual fitness differences that a simple max-heart-rate percentage ignores.
The zones typically break down as: Zone 1 (50–60% of reserve or max) for very light, warm-up intensity; Zone 2 (60–70%) for light aerobic effort often called the "fat-burning" zone; Zone 3 (70–80%) for moderate aerobic training; Zone 4 (80–90%) for hard, anaerobic-threshold effort; and Zone 5 (90–100%) for maximum, all-out exertion sustainable only briefly.
Different zones serve different training goals: lower zones build aerobic base fitness and are sustainable for long durations, while higher zones improve speed and power but can only be maintained briefly — most structured training plans deliberately mix zones rather than always training at maximum intensity.
Keep in mind that both the age-based max heart rate formula and the Karvonen adjustment are still estimates — individual variation in cardiovascular fitness, genetics, medication, and other factors mean your actual optimal training zones may differ somewhat from these calculated ranges.
What's the Karvonen formula?
It calculates zones from your heart rate reserve (max − resting) rather than max heart rate alone, giving a more personalized result.
How accurate is the 220-minus-age max heart rate formula?
It's a rough population average that can be off by 10-15 bpm or more for any individual — useful as a starting estimate, but a supervised max heart rate test is more accurate if precision matters.
Why is Karvonen considered more accurate than the simple percentage method?
It factors in your resting heart rate as a proxy for cardiovascular fitness, so two people with the same max heart rate but very different fitness levels get different, more personalized target zones.
What is Zone 2 training, and why is it popular?
Zone 2 (roughly 60-70% of heart rate reserve or max) is a light aerobic intensity that's sustainable for long durations and builds aerobic base fitness efficiently — it's gained popularity as a foundational training intensity in endurance sports.
Do I need a heart rate monitor to use these zones?
Not strictly, but it makes staying in a target zone during exercise much easier and more precise than estimating effort by feel alone.
Why do heart rate zones matter for training?
Different zones produce different physiological adaptations — lower zones build aerobic endurance, higher zones improve speed and anaerobic capacity — so training across a mix of zones is generally more effective than staying in just one.
Can medications affect my heart rate zones?
Yes — certain medications (like beta blockers) can significantly lower heart rate response to exercise, making standard heart rate zone estimates less reliable for people taking them.
What's considered a normal resting heart rate?
Roughly 60-100 bpm for most adults, with well-conditioned athletes often lower — a lower resting heart rate (within a healthy range) generally reflects better cardiovascular fitness.
Should I always train in Zone 5?
No — Zone 5 (maximum effort) can only be sustained briefly and is typically used for short, high-intensity intervals rather than the bulk of training, which usually emphasizes lower zones for sustainable, cumulative training volume.
How often should I recalculate my heart rate zones?
Recalculating periodically as fitness changes (and resting heart rate typically drops with improved cardiovascular fitness) keeps zones accurate — many people recheck every few months or after a significant change in training volume.
Can two people the same age have very different actual max heart rates?
Yes — the 220-minus-age formula is a population average, and individual max heart rate can vary by 10-15 bpm or more from that estimate even at the identical age.