Tool · Cardio
Heart rate
zones.
Your 5 training zones in beats per minute, from your age (adults) or your measured max heart rate. Add your resting heart rate for a more personal calculation.
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The 5 zones and what they're for
| Zone | % max HR | Feel | Use |
|---|---|---|---|
| Z1 · Recovery | 50–60% | Very easy | Warm-up, cool-down, recovery runs |
| Z2 · Endurance | 60–70% | Easy, you can talk | The base of endurance: most of your volume |
| Z3 · Tempo | 70–80% | Comfortably hard, short sentences | Tempo runs, active endurance |
| Z4 · Threshold | 80–90% | Hard, a few words | Threshold, long intervals, half-marathon or marathon pace for trained runners |
| Z5 · Maximal | 90–100% | Very hard, can't talk | Short intervals, 5K to 10K pace, finishing sprint |
This 5-zone split is the most common one, but not the only one: some watches and coaches use other boundaries. Keep the same system from one session to the next.
Two ways to calculate
- As a % of max heart rate: zone = max HR × percentage. Simple: all you need is your max heart rate.
- Karvonen method (heart rate reserve): zone = resting HR + (max HR − resting HR) × percentage. It takes your resting heart rate into account, and so your fitness. The calculator uses it as soon as you enter your resting heart rate.
Careful: the same percentage gives higher heart rates with heart rate reserve than with max heart rate. With the Karvonen method, the calculator's zones are therefore higher than those in the % of max HR chart: don't mix the two systems.
Estimating your max heart rate
The best max heart rate is one you have measured, for example at the end of a very hard effort with a chest strap. Without a measurement, it is estimated from age:
- Tanaka formula: 208 − 0.7 × age. Published in 2001 (Tanaka, Monahan and Seals, Journal of the American College of Cardiology), it is more accurate than the older formula. It's the one the calculator uses.
- Classic formula: 220 − age. Very well known, but it overestimates max heart rate in young adults and underestimates it more and more after 40 (about 10 beats too low at 70).
These formulas give an average: your real max heart rate can be ten or so beats away, sometimes 20 or more. If your zones feel too easy or too hard, go by feel too.
| Age | Max HR (Tanaka) | Max HR (220 − age) | Zone 2 (60–70%, Tanaka) |
|---|---|---|---|
| 20 | 194 | 200 | 116–136 |
| 25 | 191 | 195 | 115–134 |
| 30 | 187 | 190 | 112–131 |
| 35 | 184 | 185 | 110–129 |
| 40 | 180 | 180 | 108–126 |
| 45 | 177 | 175 | 106–124 |
| 50 | 173 | 170 | 104–121 |
| 55 | 170 | 165 | 102–119 |
| 60 | 166 | 160 | 100–116 |
| 65 | 163 | 155 | 98–114 |
| 70 | 159 | 150 | 95–111 |
FAQ
What is zone 2?
The easy endurance zone, between 60 and 70% of max heart rate. The effort is easy: you can hold a conversation. It's where most of your endurance is built.
How do I measure my resting heart rate?
In the morning, on waking, still lying down, for one minute. Do it several days in a row and keep the average. Many watches measure it automatically at night.
My watch shows different zones: which is right?
Neither is wrong: watches often use the same percentages, but not necessarily the same max heart rate (estimated or detected) or the same basis (% of max HR, % of heart rate reserve, % of threshold). What matters most is sticking to one system to track your progress.
With RUNESIS Training
Your fitness, read every morning.
Connect your watch: RUNESIS Training imports your workouts and your resting heart rate, and adjusts today's session to how you feel.
General guidance, not medical advice. If you have a health condition, take medication that affects the heart (beta-blockers, for example) or are returning to exercise, ask a doctor before training in the high zones.