CalcHeart Rate Training Zones
Calculate the 5 heart rate training zones based on age.
Heart Rate Training Zones Calculator: Train Smarter
Heart rate training zones divide your maximum heart rate into five distinct intensity ranges, each targeting different physiological adaptations and energy systems. Training in the correct zone ensures you get the right stimulus for your specific fitness goals, whether that’s building an aerobic base, improving endurance, or developing peak performance.
Heart Rate Training Zones Formula
Zone 1: 50–60% Max HR | Zone 2: 60–70% Max HR | Zone 3: 70–80% Max HR
Zone 4: 80–90% Max HR | Zone 5: 90–100% Max HR
First estimate your maximum heart rate using 220 − age (or a measured value from a graded exercise test). Then calculate each zone by multiplying your max HR by the corresponding percentage range. For a 35-year-old with an estimated max HR of 185 bpm: Zone 1 = 93–111 bpm (warm-up/recovery), Zone 2 = 111–130 bpm (fat burning/aerobic base), Zone 3 = 130–148 bpm (aerobic endurance), Zone 4 = 148–167 bpm (lactate threshold), Zone 5 = 167–185 bpm (maximum effort/anaerobic).
Worked Examples
Example 1: Marathon Training Plan
A 40-year-old preparing for a marathon has a max HR of 180 bpm and wants to structure weekly training across zones.
Zone 2 (60–70%): 108–126 bpm — 3 long runs per week
Zone 3 (70–80%): 126–144 bpm — 1 tempo run per week
Zone 4 (80–90%): 144–162 bpm — 1 interval session per week
This polarized approach spends 80% of training time in Zone 2 for aerobic development while using higher zones sparingly for threshold and speed work. This distribution mirrors the training patterns of elite endurance athletes.
Example 2: HIIT Session for Fat Loss
A 30-year-old woman with a max HR of 190 bpm designs a high-intensity interval training session.
Warm-up: Zone 1 (95–114 bpm) for 5 minutes
Work intervals: Zone 5 (171–190 bpm) for 30 seconds × 8 rounds
Recovery: Zone 2 (114–133 bpm) for 90 seconds between intervals
Cool-down: Zone 1 (95–114 bpm) for 5 minutes
This 28-minute session maximizes EPOC (excess post-exercise oxygen consumption), creating an elevated metabolic rate for hours after exercise. The alternating between Zone 5 and Zone 2 trains both anaerobic capacity and recovery efficiency.
Common Uses
- Structuring periodized training programs that systematically develop different energy systems over a season
- Ensuring easy days stay truly easy by keeping recovery runs in Zone 1–2
- Designing interval training protocols with precise work and recovery heart rate targets
- Monitoring training load and preventing overtraining through zone-based time distribution analysis
- Setting appropriate intensity for group fitness classes to accommodate varying fitness levels
- Tracking fitness improvements as the same pace produces a lower heart rate over time
Common Mistakes
- Spending too much time in Zone 3 (the “grey zone”), which is too hard for recovery but too easy for meaningful adaptation
- Using an inaccurate maximum heart rate estimate that shifts all zones incorrectly, leading to undertraining or overtraining
- Ignoring that zones based on max HR differ from zones based on lactate threshold, which can be 10–20 bpm different
- Not adjusting zones as fitness improves, causing training to become progressively less challenging than intended
Pro Tip
Follow the 80/20 rule: spend approximately 80% of your weekly training time in Zones 1–2 and 20% in Zones 4–5. This polarized approach, validated by research on elite endurance athletes, produces superior fitness gains compared to moderate-intensity training. Use a chest-strap heart rate monitor for accuracy, as wrist-based optical sensors can lag by 5–15 seconds during rapid intensity changes, making zone tracking less reliable during interval sessions.
Frequently Asked Questions
Lactate threshold-based zones are more accurate for serious athletes, as threshold heart rate varies independently of max HR. However, max HR zones are simpler to calculate and sufficient for recreational exercisers. If you have access to lactate threshold testing, use those values. Otherwise, max HR zones provide a reasonable approximation.
Beginners should spend most of their time in Zone 2 (60–70% max HR) for the first 8–12 weeks. This builds aerobic capacity, strengthens the cardiovascular system, and develops fat-burning efficiency without excessive fatigue or injury risk. Gradually introduce Zone 3 work after establishing an aerobic base.
Zone 5 efforts should be brief: 30 seconds to 2 minutes maximum per interval, with full recovery between efforts. Zone 5 represents near-maximal to maximal effort and cannot be sustained for long periods. Typical HIIT sessions include 6–12 Zone 5 intervals with equal or longer recovery periods in Zone 1–2.
Yes. Since maximum heart rate decreases by approximately 1 bpm per year, your absolute zone boundaries shift downward with age. Recalculate your zones annually or whenever you notice a consistent change in your max HR. However, the percentage boundaries (50–60%, 60–70%, etc.) remain the same regardless of age.