Zone 2 Heart Rate Calculator

Train smarter with the correct training zones

Zone 2 training - Building your aerobic base

Zone 2 training is the foundation of endurance performance. It develops your aerobic system, improves efficiency, and allows you to sustain effort for longer with less fatigue. Whether you're running, cycling, or training for a triathlon, spending time in Zone 2 is one of the most effective ways to improve long-term performance.

Use this zone 2 calculator to identify your personal training range and ensure you’re training at the right intensity.

Maximum Heart Rate Calculator

Calculate your heart rate training zones in seconds. Enter your age or your max heart rate below to get started.

How old are you?
or
Max heart rate (bpm)

Based on your age (21), your max heart rate is estimated at 199 bpm

Training zone calculator

Zone
Feel
Zone 1
Easy
Recovery - warm-ups and cool-downs
119-139
Zone 2
Steady
Endurance - comfortable, conversation pace
119-139
Zone 3
Moderately Hard
Aerobic - moderate pace, longer runs
159-169
Zone 4
Hard
Threshold - challenging but sustainable
169-179
Zone 5
Very Hard
VO2 Max - short, intense efforts
179-189

How is zone 2 calculated?

Zone 2 is calculated as a percentage of your maximum heart rate, representing a moderate intensity where your body can sustain effort comfortably while primarily using fat as fuel.

What should zone 2 feel like?

  • Comfortable, steady effort
  • You can hold a conversation
  • Breathing is controlled, not strained

Benefits of zone 2 training

  • Builds Aerobic Capacity. Consistent Zone 2 training strengthens your aerobic system by increasing mitochondrial density and improving oxygen delivery to working muscles. Over time, this supports improvements in VO₂ max and overall endurance performance.
  • Enhances Lactate Processing. Training in Zone 2 increases your muscles’ ability to clear and reuse lactate. This improves metabolic efficiency and allows you to maintain steady efforts without accumulating fatigue too quickly.
  • Improves Fat Utilisation. At Zone 2 intensity, your body becomes more efficient at using fat as fuel instead of relying heavily on carbohydrates. This helps preserve glycogen stores and delays fatigue during longer efforts.
  • Supports Consistency and Reduces Injury Risk. Because Zone 2 training is lower-impact and less stressful on the body, it allows for higher training volume with a reduced risk of injury. This makes it easier to train consistently - the most important factor in long-term progress
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