Heart-Rate Zone Calculator
Max HR (220−age & Tanaka) + Karvonen reserve zones
Estimate your maximum heart rate two ways — the classic 220 − age and the more accurate Tanaka 208 − 0.7 × age — then build training zones with the Karvonen reserve method: target HR = ((max HR − resting HR) × intensity%) + resting HR. Enter your age and resting heart rate to get five zones from recovery to VO2 max. A measured max beats any formula.
Source: Tanaka et al., 2001; Karvonen method.
General training guidance, not medical advice. Stop and seek advice if you feel unwell.
The formulas
Max HR (classic) = 220 − age
Max HR (Tanaka) = 208 − 0.7 × age
HRR (reserve) = max HR − resting HR
Target HR = (HRR × intensity%) + resting HR ← KarvonenWhat the zones mean
| Zone | % HRR | How it feels | Purpose |
|---|---|---|---|
| Zone 1 — Recovery | 50–60% | Very easy, conversational | Active recovery, warm-up and cool-down. |
| Zone 2 — Aerobic / endurance | 60–70% | Easy, can hold a conversation | Builds aerobic base, fat metabolism and capillary density. |
| Zone 3 — Tempo | 70–80% | Moderately hard, short sentences | Improves aerobic efficiency and stamina. |
| Zone 4 — Threshold | 80–90% | Hard, only a few words at a time | Raises lactate threshold and race pace. |
| Zone 5 — VO2 max | 90–100% | Maximal, unsustainable | Develops peak aerobic power and speed. |
Source: Standard five-zone model (Karvonen heart-rate reserve).
Match your zones to pace with the running pace calculator, and use the race time predictor to plan goal efforts.
Frequently asked questions
How do I calculate my maximum heart rate?
Two common estimates: the classic 220 − age, and the Tanaka equation 208 − 0.7 × age, which is more accurate for older adults. For a 40-year-old: 220 − 40 = 180 bpm, or 208 − 0.7 × 40 = 180 bpm. A measured max from a hard effort or lab test is more reliable than any formula.
What is the Karvonen method?
Karvonen uses heart-rate reserve (HRR), the gap between your resting and maximum heart rate, to set zones: target HR = ((max HR − resting HR) × intensity%) + resting HR. It personalises zones to your fitness because it accounts for your resting heart rate, unlike a plain percentage of max HR.
What are the five heart-rate training zones for?
Zone 1 (50–60% HRR) is recovery, Zone 2 (60–70%) builds your aerobic base, Zone 3 (70–80%) is tempo, Zone 4 (80–90%) is threshold work, and Zone 5 (90–100%) is VO2-max intervals. Most endurance training should be easy Zone 1–2, with smaller doses of hard Zone 4–5.
Should I use percentage of max HR or heart-rate reserve?
Heart-rate reserve (Karvonen) is generally preferred because it factors in your resting heart rate and better reflects true effort. Percentage of max HR is simpler but can place easy efforts too high for fit people. This calculator shows Karvonen reserve zones.