Heart Rate Zone Calculator
Calculate your five heart rate training zones using age-based estimation, a known max heart rate, or your lactate threshold.
Choose Your Method
Enables more accurate Karvonen method zones
How It Works
This calculator supports three methods for determining your training zones:
- Age-based — Estimates max HR using both the classic formula (220 − age) and the more accurate Tanaka formula (208 − 0.7 × age).
- Known Max HR — Uses your actual measured maximum heart rate for the most accurate percentage-based zones.
- Lactate Threshold (LTHR) — Calculates zones based on your lactate threshold heart rate, which better reflects individual fitness levels.
If you provide a resting heart rate, the calculator applies the Karvonen method for more personalized zone boundaries that account for your cardiovascular fitness.
Why It Matters
Training in the right heart rate zone ensures you're building the energy system you're targeting — whether that's fat-burning base fitness in Zone 2 or VO2 max capacity in Zone 5. SensAI tracks your heart rate zones during every workout and uses them to balance your weekly training load automatically.
SensAI tracks your zones automatically
Connect your wearables and let AI balance your weekly training load across all five heart rate zones.
