Target Heart Rate Calculator
Calculate your personalized target heart rate zone using the Karvonen formula, based on age, resting heart rate, and intensity.
Target Heart Rate Zone
130–172
bpm
Max Heart Rate
190 bpm
Heart Rate Reserve
120 bpm
How to Use the Target Heart Rate Calculator
Enter your age, resting heart rate, and a desired intensity range. This calculator uses the Karvonen formula: Target HR = ((Max HR − Resting HR) × %Intensity) + Resting HR. Unlike a simple percentage of max heart rate, the Karvonen method factors in your resting heart rate — your Heart Rate Reserve (HRR) — which makes it more personalized and generally considered more accurate, especially for people whose resting heart rate is unusually high or low.
Why the Karvonen Formula Is More Accurate
A simple percentage-of-max-HR method treats everyone with the same age identically, ignoring cardiovascular fitness. Two 30-year-olds with the same max heart rate but very different resting heart rates (say 50 bpm for a trained athlete versus 80 bpm for a sedentary person) actually need different target zones to achieve the same relative effort. The Karvonen formula accounts for this by working from your Heart Rate Reserve — the gap between your resting and maximum heart rate — rather than max heart rate alone.
Example
A 30-year-old with a resting heart rate of 70 bpm has a max heart rate of 190 bpm and a Heart Rate Reserve of 120 bpm. For a 50-85% intensity range, the Karvonen formula gives a target zone of (120 × 0.50) + 70 = 130 bpm to (120 × 0.85) + 70 = 172 bpm.
Common Use Cases
- Setting a personalized cardio training zone that accounts for fitness level.
- Comparing training intensity across people with different resting heart rates.
- Tracking whether a workout heart rate matches an intended training zone.
FAQs
What is the Karvonen formula?
The Karvonen formula calculates a target heart rate using your Heart Rate Reserve (max heart rate minus resting heart rate): Target HR = ((Max HR − Resting HR) × %Intensity) + Resting HR. It is considered more accurate than simply taking a percentage of max heart rate because it accounts for individual fitness via resting heart rate.
How do I find my resting heart rate?
Measure your pulse for a full minute right after waking up, before getting out of bed, on a day you feel well-rested. Average it over a few mornings for a more reliable number.
Is this a substitute for medical advice?
No — this tool gives a statistical estimate based on standard exercise-physiology formulas, not a personalized medical assessment. If you have a heart condition or are new to exercise, consult a doctor before training in these zones.