Target Heart Rate Calculator – Find Your Heart Rate Zones
Find your target heart rate zones with the Karvonen formula.
About the Target Heart Rate Calculator
What is the Target Heart Rate Calculator?
A target heart rate calculator uses the Karvonen method to map your personal aerobic training zones from your age and resting heart rate.
Why use this calculator?
Training in defined zones keeps easy sessions easy and hard sessions hard, which is how you actually build aerobic fitness efficiently.
How to use it
- Enter your age and resting heart rate (best measured on waking).
- Read your max heart rate and the four training zones.
- Use a watch or finger-pulse check to stay within the zone your workout calls for.
Formula
Target = resting + (max − resting) × intensity; max ≈ 220 − age.
The 220-age rule is a population average. Individual max values vary, so use a monitored test for precision.
Frequently Asked Questions
What beats-per-minute counts as vigorous?
Generally 70–85% of your max heart rate — use the row shown on screen for your numbers rather than a fixed figure.
Should beginners train at 85%?
No. Start in the light-to-moderate zones. Intensity builds as your fitness and recovery allow.
Is this a medical diagnosis?
No. This tool provides general wellness information only. It is not a substitute for evaluation by a qualified healthcare professional.
Why do results differ from my doctor's measurements?
Clinical measurements use calibrated equipment and professional technique. Home estimates rely on formulas and self-reported values, so small differences are normal.
How often should I recalculate?
Recheck after meaningful changes such as weight gain or loss, a new workout routine, or every few months to track trends over time.
Do these formulas apply to everyone?
Most population formulas are less accurate for athletes, pregnant people, very young children and the elderly. Use them as a general guide.
Is this calculator free to use?
Yes. Every calculator on this site is completely free, with no hidden fees, no subscriptions and no limits on how many times you can use it.
How accurate are the results?
We use standard, widely accepted formulas and calculate in your browser using double-precision arithmetic. Results are rounded for readability, so treat them as reliable estimates rather than a guarantee. Real-world factors can vary the true figure.
Can I add this calculator to my own website?
Yes. Open this calculator page and use the "Add to your website" box in the sidebar to copy a ready-made iframe snippet, then paste it into any HTML page.
Does it work on a phone or tablet?
Yes. The layout is fully responsive, so it works on desktops, laptops, tablets and mobile phones, and every input adapts to touch screens.