Zone 2 Heart Rate Calculator
Your Zone 2 range from age and resting heart rate — compared across the four most-used methods.
Sanity check: in Zone 2 you can talk in full sentences but would rather not sing. If you can only say a few words, you are above it.
Zone 2 heart rate by age
Typical ranges using the Tanaka max-HR estimate (208 − 0.7 × age). The Karvonen column assumes a resting heart rate of 60 bpm — enter yours above for a personal range.
| Age | % of max HR | Karvonen | MAF 180 |
|---|---|---|---|
| 20 | 116–136 | 140–154 | 150–160 |
| 25 | 114–133 | 138–151 | 145–155 |
| 30 | 112–131 | 136–149 | 140–150 |
| 35 | 110–128 | 134–146 | 135–145 |
| 40 | 108–126 | 132–144 | 130–140 |
| 45 | 106–124 | 130–142 | 125–135 |
| 50 | 104–121 | 128–139 | 120–130 |
| 55 | 102–119 | 126–137 | 115–125 |
| 60 | 100–116 | 124–134 | 110–120 |
| 65 | 98–114 | 122–132 | 105–115 |
| 70 | 95–111 | 119–129 | 100–110 |
How the methods work
% of max HR: 60–70% of maximum heart rate. Karvonen: 60–70% of heart-rate reserve (max − resting) added to your resting HR. MAF: 180 minus age as the ceiling, 10 beats below as the floor. Threshold: 81–89% of your lactate-threshold heart rate (Friel). All calculations happen in your browser.
What is Zone 2 heart rate?
Zone 2 is easy aerobic training — roughly 60–70% of your maximum heart rate, or just below your first lactate threshold. You can still speak in full sentences. It builds mitochondrial density and fat oxidation with little fatigue, which is why endurance athletes spend most of their training time there.
Which Zone 2 formula is most accurate?
A lab or field lactate-threshold test is most accurate. Without one, the Karvonen method (heart-rate reserve) is usually closer than a plain percentage of max HR because it accounts for your resting heart rate. The MAF 180 − age formula is a simple, conservative ceiling.
How long should Zone 2 sessions be?
Most coaches recommend 45–90 minutes per session and 2–4 sessions a week. Consistency matters more than any single long session.
Why is my Zone 2 pace so slow?
Almost everyone runs too fast at first. Keeping heart rate in Zone 2 often means jogging or even walking uphill. Pace at the same heart rate improves over weeks as your aerobic base grows.