What are your heart rate zones?
Heart rate zones split your effort into five bands by percentage of your max heart rate: zone 1 is 50–60%, zone 2 is 60–70%, zone 3 is 70–80%, zone 4 is 80–90% and zone 5 is 90–100%. For a 35-year-old with an estimated max of 184 bpm, zone 2 is 110–128 bpm. Enter your age above for your own zones. Add a measured max heart rate if you have one, and your resting heart rate to see heart rate reserve (Karvonen) zones as well.
How to use this calculator
- 1
Enter your age
The calculator estimates your max heart rate with the Tanaka formula (208 − 0.7 × age). You can switch to Gellish, Nes or the traditional 220 − age to compare.
- 2
Add a measured max heart rate (optional)
If you've hit a true max in a lab test or a hard field test, enter it. It replaces the age estimate, which can be off by about 10 bpm either way.
- 3
Add your resting heart rate (optional)
Take it lying down, first thing in the morning, or use your watch's overnight average. It adds heart rate reserve zones, which suit fit people with low resting heart rates.
- 4
Train by zone
Most easy and long sessions belong in zone 2. Keep zones 4 and 5 for planned hard sessions.
The five heart rate zones
| Zone | % max HR | How it feels | What it trains |
|---|---|---|---|
| 1 Very light | 50–60% | Very easy, breathing barely raised | Recovery, warm-up, cool-down |
| 2 Light | 60–70% | Easy; you can talk in full sentences | Aerobic base and endurance; most of your weekly volume |
| 3 Moderate | 70–80% | Steady; short sentences only | Aerobic fitness, steady longer efforts |
| 4 Hard | 80–90% | Hard; a few words at a time | Threshold: the pace you can hold for 20–60 minutes |
| 5 Maximum | 90–100% | Very hard; can't talk | VO₂ max and speed, in short intervals |
This is the standard five-zone split by percentage of max heart rate, the default in Polar's training guidance. Other systems exist: some coaches use six or seven zones, or set zones from lactate threshold heart rate. The zones here never overlap and leave no gaps, so every heartbeat falls in exactly one zone.
Zone 2 heart rate by age
Zone 2 (60–70% of max heart rate), using the Tanaka formula and the traditional 220 − age for comparison:
| Age | Max HR (Tanaka) | Zone 2 (Tanaka) | Max HR (220 − age) | Zone 2 (220 − age) |
|---|---|---|---|---|
| 20 | 194 | 116–135 | 200 | 120–139 |
| 30 | 187 | 112–130 | 190 | 114–132 |
| 40 | 180 | 108–125 | 180 | 108–125 |
| 50 | 173 | 104–120 | 170 | 102–118 |
| 60 | 166 | 100–115 | 160 | 96–111 |
| 70 | 159 | 95–110 | 150 | 90–104 |
The two formulas agree at 40 and drift apart with age: 220 − age gives a 70-year-old a max 9 bpm lower than Tanaka. Tanaka's study found the old rule underestimates max heart rate in older adults, which would make their zones too low.
"Zone 2" also has a second meaning. In exercise physiology it often means the intensity just below your first lactate threshold, which varies from person to person and can sit above 70% of max heart rate in trained people. The practical check is the same either way: in zone 2 you can hold a full conversation. Read more in our guide to zone 2 training.
Max heart rate formulas compared
| Formula | Equation | Based on | At age 40 |
|---|---|---|---|
| Tanaka (2001) | 208 − 0.7 × age | Meta-analysis of 351 studies, 18,712 people, plus a lab study of 514 | 180 |
| Gellish (2007) | 207 − 0.7 × age | 908 max tests in 132 people tracked over 25 years | 179 |
| Nes (2013) | 211 − 0.64 × age | 3,320 healthy adults in Norway's HUNT study | 185 |
| Traditional | 220 − age | Rule of thumb; not from a regression study | 180 |
No age formula is precise for one person. In the HUNT study, the standard error of the age prediction was 10.8 bpm, so roughly a third of people are more than 10 bpm away from their predicted max. Tanaka and Nes found that sex and fitness made little difference to the prediction. If your zones feel wrong, a measured max heart rate fixes most of the problem.
Max heart rate vs heart rate reserve (Karvonen) zones
Percent-of-max zones use only your max heart rate. The Karvonen method uses your heart rate reserve, the gap between resting and max: target = resting HR + percentage × (max HR − resting HR). Because it starts from your resting heart rate, every zone sits higher.
Example, a 35-year-old with a resting heart rate of 60: max-HR zone 2 is 110–128 bpm, while heart-rate-reserve zone 2 is 134–146 bpm. Fit people with low resting heart rates usually find the Karvonen numbers closer to how easy running actually feels.
The two scales aren't interchangeable. The ACSM's exercise guidelines class moderate intensity as 64–76% of max heart rate or 40–59% of heart rate reserve, and vigorous as 77–95% of max or 60–89% of reserve.
Frequently asked questions
How do I calculate my heart rate zones?
Find your max heart rate, then take percentages of it: zone 1 is 50–60%, zone 2 is 60–70%, zone 3 is 70–80%, zone 4 is 80–90% and zone 5 is 90–100%. If you know your resting heart rate, the heart rate reserve (Karvonen) method is often more accurate: resting HR + percentage × (max HR − resting HR).
What is my zone 2 heart rate?
On the five-zone model, zone 2 is 60–70% of your max heart rate. For a 40-year-old with an estimated max of 180 bpm, that's about 108–125 bpm. With a resting heart rate, the Karvonen method gives a higher range. Whichever number you use, zone 2 should feel easy enough to hold a full conversation.
Is 220 minus age accurate?
Only roughly. 220 − age wasn't derived from a large study, and it underestimates max heart rate in older adults. The Tanaka formula (208 − 0.7 × age), based on data from 18,712 people, is a better default. Any age formula can still be off by about 10 bpm for an individual; the HUNT study measured a standard error of 10.8 bpm.
Should I use max heart rate or heart rate reserve zones?
Use heart rate reserve (Karvonen) zones if you know your resting heart rate, especially if you're fit and your resting heart rate is low. Percent-of-max zones ignore resting heart rate, so for fit people they can make easy zones feel too easy. Percent-of-max zones are simpler and are what most watches use by default.
How do I find my real max heart rate?
The most accurate way is a lab exercise test. A field test also works for healthy, already-active people: after a thorough warm-up, run or cycle several hard efforts of 2–3 minutes, finishing the last one all-out, and take the highest reading from a chest strap. Talk to a doctor first if you have heart symptoms, a heart condition or you're new to exercise.
Why is my heart rate higher than my zones during easy runs?
Heat, dehydration, poor sleep, caffeine, stress and hills all raise heart rate at the same effort, and wrist sensors can misread. An age-based max can also simply be wrong for you by 10 bpm or more. If an easy, conversational effort keeps reading as zone 3, test your max heart rate or switch to Karvonen zones.