How your five heart rate zones are calculated
The tool splits your heart rate into five bands of maximum heart rate: 50–60%, 60–70%, 70–80%, 80–90% and 90–100%. If you do not know your maximum, it is estimated as 208 minus 0.7 times your age 1.
With your resting heart rate, the tool can also use heart-rate reserve, the gap between maximum and resting heart rate, and place each zone that share of the gap above your resting rate 2.
Zone systems are conventions. Researchers often describe intensity in three zones, and five-zone schemes draw their lines in different places 3. Treat the boundaries as guides, not physiology.
How to use your zones
Spend most of your endurance time in zones 1 and 2: in well-trained endurance athletes, most sessions are done at low intensity 3. Check easy days with the talk test; the point where talking first gets hard matches the ventilatory threshold 4.
Use zones 4 and 5 for short, planned intervals. Our guides Move in Zone 2 and Build your VO2max explain how to combine them.
| Age | Max HR | Zone 2 |
|---|---|---|
| 25 | 191 bpm | 114–133 bpm |
| 30 | 187 bpm | 112–131 bpm |
| 35 | 184 bpm | 110–128 bpm |
| 40 | 180 bpm | 108–126 bpm |
| 45 | 177 bpm | 106–124 bpm |
| 50 | 173 bpm | 104–121 bpm |
| 55 | 170 bpm | 102–119 bpm |
| 60 | 166 bpm | 100–116 bpm |
| 65 | 163 bpm | 98–114 bpm |
| 70 | 159 bpm | 95–111 bpm |
Questions people ask
How do I calculate my heart rate zones?
Estimate your maximum as 208 minus 0.7 times your age 1, or use a measured maximum, then take 50–60%, 60–70%, 70–80%, 80–90% and 90–100% of it. With a resting heart rate you can apply the same percentages to your heart-rate reserve instead 2.
Which zone should I train in most?
For most people, the easy zones. In well-trained endurance athletes, the large majority of sessions are low intensity, with a smaller share of hard work 3.
Percent of maximum or heart-rate reserve: which is better?
Heart-rate reserve takes your resting heart rate into account 2, so it fits fitter people with a low resting rate better. Percent of maximum is simpler. Pick one and stay with it.
How do I find my real maximum heart rate?
The formula gives an average for your age 1. A supervised maximal test, or the highest reading at the end of an all-out race, gives you a personal number. Do not chase a maximum if you have heart problems or have been told to avoid hard exercise.
Sources
- Tanaka H, Monahan KD, Seals DR. Age-predicted maximal heart rate revisited. J Am Coll Cardiol. 2001;37(1):153–156.
- Karvonen MJ, Kentala E, Mustala O. The effects of training on heart rate; a longitudinal study. Ann Med Exp Biol Fenn. 1957;35(3):307–315.
- Seiler S. What is best practice for training intensity and duration distribution in endurance athletes? Int J Sports Physiol Perform. 2010;5(3):276–291.
- Persinger R, Foster C, Gibson M, Fater DCW, Porcari JP. Consistency of the talk test for exercise prescription. Med Sci Sports Exerc. 2004;36(9):1632–1636.