# Heart rate zone calculator: five training zones from your age

Heart rate zones are bands of effort based on your maximum heart rate. A common estimate of maximum is 208 − 0.7 × age (Tanaka). With a resting heart rate, the Karvonen method sets zones on your heart rate reserve, which fits trained people better. Zone 2 is the easy, conversational zone most endurance training lives in.

## How it works

### Maximum heart rate

Tanaka: 208 − 0.7 × age. The older 220 − age is simpler but less accurate in older adults. A field test or a recent hard race gives a better number.

### Zones

Zone 1: 50–60%, zone 2: 60–70%, zone 3: 70–80%, zone 4: 80–90%, zone 5: 90–100% of maximum (or of reserve with Karvonen).

### Karvonen

Target = resting + percentage × (maximum − resting). It moves the zones up for people with a low resting heart rate.

## Questions

### What is zone 2 training?

Steady, conversational effort at about 60% to 70% of maximum heart rate. It builds aerobic fitness with little fatigue.

### Why does my watch show different zones?

Watches use their own formulas or your measured maximum. Use one method consistently.

### Do medications change heart rate zones?

Some, such as beta blockers, lower heart rate. If you take one, ask your clinician how to judge effort.

## Sources

- [Tanaka H et al. Age-predicted maximal heart rate revisited. J Am Coll Cardiol 2001](https://pubmed.ncbi.nlm.nih.gov/11153730/)

Accurate as of November 12, 2026.

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revns gives training guidance, not medical advice.