Heart Rate Zone Calculator
Calculate your 5 cardiovascular training zones based on your age. Optionally enter your resting heart rate to use the Karvonen (Heart Rate Reserve) method for more personalised zones. Used by athletes, coaches, and cardiologists.
Key Capabilities
How is maximum heart rate calculated?
The tool uses the widely adopted Fox & Haskell formula: Max HR = 220 − Age. This is a population average and individual maximum heart rate can vary by ±10–20 bpm. The Tanaka formula (208 − 0.7 × Age) may be more accurate for older adults.
What is the Karvonen method?
The Karvonen or Heart Rate Reserve (HRR) method calculates zones using both maximum and resting heart rate: Target HR = ((Max HR − Resting HR) × % intensity) + Resting HR. This produces more personalised zones than simple percentage-of-max calculations.
What are the 5 heart rate training zones used for?
Zone 1 (50–60%): active recovery. Zone 2 (60–70%): fat burning and aerobic base. Zone 3 (70–80%): cardiovascular fitness. Zone 4 (80–90%): anaerobic threshold training. Zone 5 (90–100%): peak performance sprints. Most endurance training recommendations target Zone 2.
How to Use
Upload your medical document
Open the Heart Rate Zone Calculator tool and upload your medical document (prescription, lab report, or medical record). Your data stays in your browser — zero server uploads.
AI analysis begins
The tool analyzes your document using specialized medical OCR models trained on healthcare documents. This typically takes 3-8 seconds.
Review extracted information
Review the structured medical information extracted from your document. Copy results or download for your records.
Frequently Asked Questions
How is maximum heart rate calculated?
The tool uses the widely adopted Fox & Haskell formula: Max HR = 220 − Age. This is a population average and individual maximum heart rate can vary by ±10–20 bpm. The Tanaka formula (208 − 0.7 × Age) may be more accurate for older adults.
What is the Karvonen method?
The Karvonen or Heart Rate Reserve (HRR) method calculates zones using both maximum and resting heart rate: Target HR = ((Max HR − Resting HR) × % intensity) + Resting HR. This produces more personalised zones than simple percentage-of-max calculations.
What are the 5 heart rate training zones used for?
Zone 1 (50–60%): active recovery. Zone 2 (60–70%): fat burning and aerobic base. Zone 3 (70–80%): cardiovascular fitness. Zone 4 (80–90%): anaerobic threshold training. Zone 5 (90–100%): peak performance sprints. Most endurance training recommendations target Zone 2.
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