What next?
Zones tell you how hard. These tell you how far, how fast and how to recover.
How to use this calculator
- Enter your age.
- Add your resting heart rate for more accurate zones (optional).
- Read your maximum heart rate and training zones.
What your result means
The zones are target heart-rate bands for different intensities, from easy recovery to hard intervals. They are based on an estimated maximum heart rate (refined by your resting rate if given), so they are approximate — a lab test is exact. Let perceived effort guide you too.
Why this one is different
Five zone rows come back, each with a beats-per-minute range and a one-line purpose, so the readout is a session plan rather than a single ceiling figure. A Method row names the formula actually used and a Resting rate row shows the input that selected it — which means you can tell at a glance whether the zones in front of you are personalised or generic.
Train smarter with heart-rate zones
Your maximum heart rate is estimated as 220 minus your age. Training zones are then bands within that maximum, each targeting a different adaptation — easy recovery, fat-burning endurance, aerobic fitness, lactate threshold and top-end speed.
If you know your resting heart rate, the Karvonen method gives more personal zones by working from your heart-rate reserve (the gap between resting and maximum) rather than raw percentages of maximum. Leave resting at zero to use the simpler method.
Formula
Zones are fixed percentage bands of either the maximum or the heart-rate reserve.
Example calculation
Age 30, resting heart rate 60 bpm — Zone 2 (60–70% reserve):
Reserve = 190 − 60 = 130
Lower = 0.60 × 130 + 60 = 138
Upper = 0.70 × 130 + 60 = 151
Zone 2 ≈ 138–151 bpm
Frequently asked questions
How accurate is 220 minus age?＋
It is a population average and can be off by 10–15 bpm for any individual. For precise zones, a lab test or a maximal effort test gives your true maximum, but 220−age is fine for general training.
Which zone should I train in?＋
Most endurance training should sit in zones 2–3, with occasional harder sessions in zone 4–5. Spending too long in the high zones without recovery raises injury and burnout risk.
What is the Karvonen method?＋
It builds zones from heart rate reserve, the gap between resting and maximum heart rate, rather than from maximum alone. Including your resting rate personalises the zones, which matters most for fitter people with low resting rates.
How do I find my resting heart rate?＋
Measure it first thing in the morning before getting up, on three or four days, and take the average. A wrist tracker's overnight low is a reasonable substitute.
Should every session be in the same zone?＋
No. Most endurance plans keep the bulk of training easy, in zones 1-2, with a smaller share of hard work in zones 4-5. Spending every session in the middle is the classic way to accumulate fatigue without gaining fitness.
Why is my heart rate higher than usual at the same effort?＋
Heat, dehydration, illness, poor sleep, caffeine and stress all raise heart rate for a given pace. If the gap persists for several days, treat it as a sign to back off.
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Assumptions & limitations
Every figure here comes from a simplified model. Keep these limits in mind when reading your result:
- Maximum heart rate is estimated (220 − age, and the Tanaka formula), which can be off by 10–12 bpm.
- A field or lab test gives a far more personal figure.
- Some medications change your heart-rate response — check with a doctor.