# Free online heart rate zones calculator

> Heart rate training zones divide exercise intensity into five bands tied to specific beats per minute. This calculator shows your five zones using the Karvonen or % max HR method.

Calculate your 5 heart rate training zones using the Karvonen heart rate reserve method or simple percentage of max HR, based on your age and resting heart rate.

**Interactive version:** https://onlinecalculator.me/health/heart-rate-zones/
**Category:** Health

## How to use

1. Enter your age — used to estimate max HR with 220 − age.
2. Enter your resting heart rate (measure it first thing in the morning for accuracy).
3. Choose Karvonen (recommended) or % Max HR.
4. The five training zones appear instantly in the table below.

## The formulas

**Maximum heart rate (standard)**

```
Max HR = 220 − age
```

**Karvonen method**

```
HR Reserve = Max HR − Resting HR
Target HR  = (HR Reserve × intensity%) + Resting HR
```

**Percentage of max HR**

```
Target HR = Max HR × intensity%
```

Zone intensities:

| Zone | Name              | Intensity range |
|------|-------------------|-----------------|
| 1    | Recovery          | 50–60%          |
| 2    | Aerobic           | 60–70%          |
| 3    | Tempo             | 70–80%          |
| 4    | Lactate Threshold | 80–90%          |
| 5    | Max Effort        | 90–100%         |

## Worked example

Age 30, resting HR 60 bpm, Karvonen method:

- Max HR = 220 − 30 = 190 bpm
- HR Reserve = 190 − 60 = 130 bpm
- Zone 1: 50% × 130 + 60 = **125 bpm** to 60% × 130 + 60 = **138 bpm**
- Zone 2: **138–151 bpm**
- Zone 3: **151–164 bpm**
- Zone 4: **164–177 bpm**
- Zone 5: **177–190 bpm**

## Notes

- The 220 − age formula is an estimate with a standard deviation of about 10–12 bpm. Individual max HR can vary significantly.
- For accurate zones, consider a field test: run all-out for 1 mile and note your peak heart rate.
- A heart rate monitor or GPS watch will give more reliable in-workout data than perceived exertion alone.

## Frequently asked questions

### What are heart rate training zones?

Training zones divide exercise intensity into five bands, from light recovery (Zone 1) to maximum effort (Zone 5). Each zone targets different energy systems — fat burning, aerobic capacity, lactate threshold — so athletes can train smarter by targeting the right zone for each session.

### What is the Karvonen method?

The Karvonen formula uses Heart Rate Reserve (HRR = max HR − resting HR) to calculate zones: Target HR = (HRR × intensity%) + resting HR. Because it accounts for your resting heart rate, it produces more personalized zones than a simple percentage of max HR.

### What is the percentage of max HR method?

The simpler method calculates zones as a straight percentage of your estimated maximum heart rate (220 − age). It does not account for resting heart rate, so it may be less accurate for trained athletes with a low resting HR.

### How is max heart rate estimated?

This calculator uses the standard formula: max HR = 220 − age. You can also enter a known max HR if you have a recent lab or field test result.

### Which method should I use?

For trained athletes or anyone with a resting heart rate well below average, the Karvonen method is more accurate. For general fitness guidance, either method works. If you have had a VO2 max test, use those laboratory zones instead.

### How do I use the Share button?

Share copies the plain page URL. Share with my numbers copies a URL with your age, resting HR, and method included, so anyone can open the link and see your zones.

## Sources

- [Target Heart Rates Chart](https://www.heart.org/en/healthy-living/fitness/fitness-basics/target-heart-rates) — American Heart Association
- [Age-predicted maximal heart rate revisited](https://pubmed.ncbi.nlm.nih.gov/11153730/) — Journal of the American College of Cardiology

## Related calculators

- [Max heart rate calculator](https://onlinecalculator.me/health/max-hr/) — Compare four different max HR formulas and see target zone ranges.
- [Running pace calculator](https://onlinecalculator.me/health/running-pace/) — Convert between pace, speed, and distance for running.
- [Calories burned calculator](https://onlinecalculator.me/health/calories-burned/) — Estimate calories burned during exercise by activity and weight.
- [BMR calculator](https://onlinecalculator.me/health/bmr/) — Calculate your basal metabolic rate to understand calorie needs.
- [TDEE calculator](https://onlinecalculator.me/health/tdee/) — Find your total daily energy expenditure including activity level.

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