In short: heart-rate zones describe how hard you are working as a share of your maximum heart rate. This calculator estimates your maximum from your age (220 − age, or the Tanaka formula 208 − 0.7 × age), and if you enter your resting heart rate it uses the Karvonen method, which accounts for your fitness. The result is five ranges you can use on any watch or chest strap. It is an estimate: real maximum heart rates vary by ten beats or more between people of the same age.
Two formulas, shown
220 − age is the classic; Tanaka (208 − 0.7 × age) fits older adults better. You see both.
Karvonen with resting pulse
Add your morning resting heart rate and the zones adapt to your fitness, not only your age.
Use it with your watch
Set the zones in your device, then let Anpheros Daily keep the sessions next to sleep and recovery.
How to use it
- Enter your age.
- If you know it, enter your resting heart rate, measured on waking, before getting up.
- Read the five zones. Copy them into your watch or your training notes.
What the zones mean
| Zone | % of maximum (or of reserve) | How it feels | Typical use |
|---|---|---|---|
| 1 | 50–60% | Very easy, full conversation | Warm-up, recovery days |
| 2 | 60–70% | Easy, sentences | Most endurance training |
| 3 | 70–80% | Moderate, short sentences | Tempo work |
| 4 | 80–90% | Hard, a few words | Intervals, threshold |
| 5 | 90–100% | Very hard, no talking | Short efforts, sprints |
Why the numbers are estimates
Maximum heart rate is set by genetics and age, not fitness, and the spread at any age is wide: the formulas describe an average person, and about a third of people fall more than ten beats away from the estimate. Fitter people have a lower resting heart rate, which is why the Karvonen method (zones as a share of the gap between resting and maximum) often matches how training feels better than age alone. Some medicines and some heart conditions change heart rate at rest and during effort; if that applies to you, use the zones your doctor or cardiac rehabilitation team gives you, not these. The tool does not say whether a heart rate is normal and does not give health advice.
Frequently asked questions
Which formula should I use?
If you are under about 40 the two formulas give similar results; over 40, Tanaka tends to be closer to measured values. With a resting heart rate, Karvonen is the better guide for training. Any of them is a starting point; adjust to how the efforts feel.
My watch gives different zones. Which is right?
Watches use their own formulas, sometimes with a measured or estimated maximum from your workouts. If your watch has seen a maximal effort, its number is likely closer to reality than an age formula. Pick one source and stay consistent.
What is a normal resting heart rate?
Most adults sit between 60 and 100 beats per minute at rest; endurance-trained people are often lower. What matters for recovery is your own baseline and changes from it, not the population range. Talk to your doctor about a resting heart rate that is persistently unusual for you, or about palpitations, dizziness or chest symptoms.
Can I use this for walking or cycling?
Yes; zones describe effort, not the activity. Cycling and swimming maximum heart rates are usually a few beats lower than running, so expect zones to feel slightly different between sports.
Is zone training suitable for everyone?
The zones are a general description of effort. People with heart conditions, those on medicines that affect heart rate, and anyone starting exercise after a long break or an illness should follow the guidance of their doctor or rehabilitation team.
