Calculate your maximum heart rate

Your maximum heart rate (HRmax) is the highest number of beats per minute your heart can achieve at peak physical exertion. This single number is the cornerstone of any structured cardio training program, because all five training zones — from gentle recovery to maximum sprint effort — are defined as percentages of HRmax. Whether you are training for your first 5K, preparing for a marathon, cycling through mountain stages, or simply trying to improve your cardiovascular health, knowing your HRmax allows you to train smarter, not just harder.

The most accurate way to determine HRmax is a medically supervised maximal stress test performed on a treadmill or cycle ergometer with electrocardiographic monitoring. However, two widely validated formulas allow you to estimate HRmax from your age alone with sufficient accuracy for practical training purposes: the classic Fox-Haskell formula (popularized in 1971) and the Tanaka formula (2001), which has been shown in research to be more accurate across a broad age range, particularly for physically active adults over 40.

How does the maximum heart rate calculation work?

Both formulas require only one variable:

• Age: in whole years. The only input needed for either formula.
• Formula choice: Classic (Fox-Haskell) or Tanaka — the latter is generally preferred for active adults and those over 40.

Classic formula (Fox-Haskell, 1971): HRmax = 220 – age

Tanaka formula (2001): HRmax = 208 – 0.7 × age

Once you have your estimated HRmax, define your five training zones as follows:

• Zone 1 (50–60%): Active recovery, very light effort, suitable for warm-ups and cool-downs.
• Zone 2 (60–70%): Fat-burning zone, aerobic base building, easy conversation possible. Ideal for long, slow runs and endurance rides.
• Zone 3 (70–80%): Aerobic fitness, tempo training, improves cardiovascular efficiency.
• Zone 4 (80–90%): Lactate threshold training, hard sustained effort, improves speed and race performance.
• Zone 5 (90–100%): VO2max training, maximum effort intervals and sprints, very short durations only.

These zones are the framework used by professional coaches, sports physiologists, and elite athletes to plan periodized training cycles that balance stimulus, recovery, and progression.

Concrete example

Let's calculate the training zones for a 38-year-old recreational runner who wants to train more intelligently for an upcoming half marathon.

Classic formula: HRmax = 220 – 38 = 182 bpm.

Tanaka formula: HRmax = 208 – 0.7 × 38 = 208 – 26.6 = 181.4 bpm (rounded to 181 bpm).

Using HRmax = 182 bpm (classic), here are the five zones:

Zone 1 (50–60%): 91–109 bpm — recovery runs, warm-ups.

Zone 2 (60–70%): 109–127 bpm — long easy runs, base building. This is where most of the runner's weekly mileage should be accumulated (ideally 70–80% of total volume).

Zone 3 (70–80%): 127–146 bpm — moderate tempo runs, marathon race pace for many runners at this level.

Zone 4 (80–90%): 146–164 bpm — threshold intervals, half marathon race effort. Use sparingly: 1–2 sessions per week maximum.

Zone 5 (90–100%): 164–182 bpm — short speed intervals, maximum effort. Never exceed 10–15% of weekly training volume in this zone.

For context: during a half marathon race, this runner might sustain a heart rate of approximately 155–165 bpm — solidly in Zone 4, which is the physiological engine of distance racing performance. Knowing this in advance allows for smarter pacing strategy on race day.

Frequently asked questions