Heart rate zone calculator
Enter your age and this calculator returns your five heart rate training zones in beats per minute, from easy recovery to max effort. Add your resting heart rate and it switches to the more precise Karvonen method, which personalizes the zones to your fitness.
| Zone | Intensity | % range | bpm | Used for |
|---|---|---|---|---|
| Zone 1 | Recovery | 50–60% | — | Warm-up, cool-down, easy days |
| Zone 2 | Fat burn / base | 60–70% | — | Long easy cardio, aerobic base |
| Zone 3 | Aerobic | 70–80% | — | Steady tempo work |
| Zone 4 | Threshold | 80–90% | — | Hard intervals |
| Zone 5 | Max effort | 90–100% | — | Short sprints, finishers |
Formula-based zones are estimates: real maximum heart rate varies between people of the same age. If a zone feels wildly off against perceived effort, trust the effort.
What heart rate zones are
Heart rate zones split the range between rest and maximum into five intensity bands, each with a different training effect. Low zones build your aerobic base and speed up recovery, middle zones develop endurance, and the top zones train speed and maximal capacity. Training in a deliberate zone keeps easy days actually easy and hard days actually hard.
Tanaka vs Karvonen
With age only, the calculator estimates max heart rate as 208 − 0.7 × age (Tanaka), a formula derived from a meta-analysis of thousands of measurements. With a resting heart rate it uses Karvonen: each zone is a percentage of your heart rate reserve, the gap between resting and max, added back on top of resting. Two people of the same age with different fitness get meaningfully different Karvonen zones, which is the point.
Zones for people who lift
If your main training is the gym, use zones for the cardio around it: zone 2 sessions on rest days build work capacity without eating into recovery, and short zone 4 intervals once a week cover conditioning. During lifting itself, heart rate jumps and falls with every set, so program your bar work by weight and reps, not by pulse. APX handles that side: a structured gym plan with rest timers and set logging.
Method and sources
The two formulas behind this calculator come from published research: Tanaka for estimating maximum heart rate from age, Karvonen for building zones from your heart rate reserve.
Age-based formulas describe a population average. Measured maximum heart rate varies by roughly 10 beats either way at the same age, so treat the zones as a starting point and adjust against perceived effort. The 5-zone percentage bands themselves are a training convention, not a research finding.
- Tanaka H, Monahan KD, Seals DR (2001). Age-predicted maximal heart rate revisited. Journal of the American College of Cardiology, 37(1), 153–156 Used for: the maximum heart rate estimate, 208 − 0.7 × age, a meta-analysis of 351 studies that supersedes 220 − age
- Karvonen MJ, Kentala E, Mustala O (1957). The effects of training on heart rate: a longitudinal study. Annales Medicinae Experimentalis et Biologiae Fenniae, 35(3), 307–315 Used for: the heart rate reserve method used when you enter a resting heart rate
Frequently asked questions
Zones are percentage bands of your maximum heart rate. This calculator estimates max heart rate with the Tanaka formula, 208 minus 0.7 times age, which tracks measured values better than the classic 220 minus age. If you enter a resting heart rate, it switches to the Karvonen method, which builds zones from your heart rate reserve and is more individual.
Zone 2, roughly 60 to 70% of max heart rate, uses the highest share of fat as fuel, which is why it is called the fat burn zone. Total calories still matter more than the fuel mix: harder zones burn more energy per minute. For body composition, training volume and diet decide the outcome, not the zone label.
Lifting is interval work by nature: heart rate spikes during a set and recovers between sets, so chasing a fixed zone under the bar is not useful. Zones matter for your cardio sessions. A common structure for gym-goers is most cardio in zone 2 with occasional zone 4 intervals, which supports recovery between lifting days instead of competing with them.
It is a population estimate: real maxes vary by 10 or more beats either way at the same age. Formulas are fine for setting training zones, and entering your resting heart rate makes them noticeably more personal. If you own a chest strap and want precision, a field max test or lab test beats any formula.
Train with structure, not guesswork
APX plans your gym sessions and logs every set. Cardio zones are yours, the bar is ours.
Download APX free