Maximum Heart Rate Calculator

Why maximum heart rate matters

Maximum heart rate is the highest number of beats per minute your heart can achieve during all-out exercise. It is a key variable in setting training zones — the intensity ranges associated with different physiological adaptations, from fat-burning aerobic base work (Zone 2) to VO₂ max intervals (Zone 5).

HR max is primarily determined by age and genetics. Unlike resting heart rate or stroke volume, it responds very little to training. This means your training zones will change gradually as you age, even if your fitness improves.

Formula comparison

Fox (1971): 220 − age. The most widely cited formula, but studies show it can underestimate HR max in older adults and overestimate it in younger adults.

Tanaka (2001): 208 − 0.7 × age. Derived from a meta-analysis of 351 studies and over 18,000 subjects. Generally considered more accurate than the Fox formula across the adult lifespan.

Gulati (2010): 206 − 0.88 × age. Validated specifically in women during exercise stress testing. Recommended for females.

Nes (2013): 211 − 0.64 × age. Derived from the HUNT study in Norway; performs well for physically active individuals.

Training zones

The five zones are defined as percentages of HR max. Zone 1 (50–60%) is active recovery. Zone 2 (60–70%) is aerobic base and fat-burning. Zone 3 (70–80%) is sustained aerobic effort. Zone 4 (80–90%) is anaerobic threshold training. Zone 5 (90–100%) is maximum intensity for short intervals.

Zone 2 training has received particular attention in endurance sports — long, easy sessions below the aerobic threshold appear to drive substantial aerobic adaptations while minimising recovery cost.