Heart Rate Training Zones Calculator Formula
Understand the math behind the heart rate training zones calculator. Each variable explained with a worked example.
Formulas Used
Zone 1 Recovery (50%)
zone1_low = round(hrr * 0.50 + resting_hr)Zone 2 Aerobic (60%)
zone2_low = round(hrr * 0.60 + resting_hr)Zone 3 Tempo (70%)
zone3_low = round(hrr * 0.70 + resting_hr)Zone 4 Threshold (80%)
zone4_low = round(hrr * 0.80 + resting_hr)Zone 5 Maximum (90%)
zone5_low = round(hrr * 0.90 + resting_hr)Max Heart Rate
max_heart_rate = max_hrVariables
| Variable | Description | Default |
|---|---|---|
age | Age(years) | 30 |
resting_hr | Resting Heart Rate(bpm) | 60 |
max_hr | Derived value= 220 - age | calculated |
hrr | Derived value= max_hr - resting_hr | calculated |
How It Works
Heart Rate Zones (Karvonen Method)
Target HR = (Max HR - Resting HR) x Intensity% + Resting HR
Five Training Zones
Worked Example
A 30-year-old with a resting HR of 60 bpm.
- 01Max HR = 220 - 30 = 190
- 02HRR = 190 - 60 = 130
- 03Zone 2 low = 130 x 0.60 + 60 = 138 bpm
- 04Zone 4 low = 130 x 0.80 + 60 = 164 bpm
Frequently Asked Questions
Which zone should I train in?
Most of your training (about 80%) should be in Zone 2 for building aerobic base. Harder sessions in Zones 4-5 should make up about 20% of training time.
Why use the Karvonen method?
The Karvonen method accounts for resting heart rate, making zones more personalized than simple percentage-of-max methods.
How do I find my resting heart rate?
Measure your pulse first thing in the morning before getting out of bed. Count beats for 60 seconds on three consecutive days and average the results.
Learn More
Guide
Heart Rate Zones Explained: Train Smarter with Zone-Based Exercise
Learn about the five heart rate training zones, how to calculate them, and how to use zone-based training to improve endurance, burn fat, and boost performance.
Ready to run the numbers?
Open Heart Rate Training Zones Calculator