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Heart Rate Zones.

Calculate target heart rate zones for training

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Train in the Right Zone

Heart rate zones split your effort into five bands, each suited to a different training purpose. Knowing your zones helps you match intensity to the session you intended.

Your Heart Rate Metrics

190

Max HR (bpm)

133

Target HR (bpm)

130

Heart rate reserve (bpm)

Training Zones

Zone 1 — Recovery

Very easy effort for warm-ups, cool-downs, and active recovery.

125 - 138 bpm

50-60% intensity

Zone 2 — Endurance

Comfortable pace you can hold for hours while still holding a conversation.

138 - 151 bpm

60-70% intensity

Zone 3 — Aerobic

Steady, moderately hard work that builds aerobic fitness.

151 - 164 bpm

70-80% intensity

Zone 4 — Threshold

Hard effort near the point where breathing becomes laboured.

164 - 177 bpm

80-90% intensity

Zone 5 — Maximum

All-out intervals sustainable only for short bursts.

177 - 190 bpm

90-100% intensity

Recovery zone: 125-138 bpm

Recovery zone

125-138 bpm
Fat burn zone: 138-151 bpm

Fat burn zone

138-151 bpm
Cardio zone: 151-164 bpm

Cardio zone

151-164 bpm

Training Tips

  • Most endurance training sits in zones 1 and 2, with harder work kept short.
  • Zone 2 work builds the aerobic base that faster sessions are built on.
  • Leave recovery days between zone 4 and 5 sessions.
  • Heat, fatigue, caffeine, and stress all shift your heart rate for a given effort.

How to Measure Your Resting Heart Rate

  • Measure first thing in the morning, before getting out of bed.
  • Count beats at your wrist or neck for 60 seconds.
  • Take readings on several mornings and use the average.
  • Avoid measuring after caffeine, alcohol, or a poor night's sleep.
  • A chest strap or fitness tracker gives more consistent readings than counting.

Cite this calculator

Canonical URL: https://mathify.one/en/fitness/heart-rate

Cite as: Mathify. (2026). Heart Rate Zones. https://mathify.one/en/fitness/heart-rate

Use Cases

Optimize Your Training Intensity

Determine which heart rate zone to target for specific goals like endurance, fat burning, or speed work. This helps you train more effectively and avoid overtraining.

Example: A runner aiming to improve endurance can target Zone 2 for long runs.

Monitor Workout Progress

Use the zones to track your effort during workouts and ensure you're progressing. Over time, you may need to recalculate as your fitness improves.

Example: Check if your easy runs fall within Zone 2 to build aerobic base.

Frequently Asked Questions

How is my maximum heart rate calculated?
The calculator estimates your maximum heart rate using a common formula based on your age. It then uses this value to define the five heart rate training zones, each representing a percentage range of your max.
What are the five heart rate training zones?
The five zones are typically: Zone 1 (very light, 50-60% of max), Zone 2 (light, 60-70%), Zone 3 (moderate, 70-80%), Zone 4 (hard, 80-90%), and Zone 5 (maximum, 90-100%). Each zone corresponds to different training benefits.
Can I use this calculator for any type of exercise?
Yes, the heart rate zones are based on your maximum heart rate and can be applied to any aerobic activity like running, cycling, or swimming. However, individual variations may exist, so use the zones as a general guide.

Tips & Common Mistakes

Tips

  • Use a heart rate monitor or fitness tracker to accurately measure your heart rate during exercise.
  • Recalculate your zones periodically, especially if you are new to exercise or have significant fitness changes.
  • Remember that the maximum heart rate formula is an estimate; individual variations exist.
  • Combine heart rate zone training with perceived exertion for a balanced approach.

Common Mistakes to Avoid

  • Assuming the calculated maximum heart rate is exact; it's an estimate and may differ from your actual max.
  • Training too hard in high zones without proper base building, which can lead to burnout or injury.
  • Ignoring rest and recovery; heart rate zones are for training, but rest is crucial for progress.

Last updated: August 13, 2026