This Karvonen formula calculator finds your target training heart rate using heart rate reserve, which accounts for your resting heart rate. Enter the values above.
Formula
Target HR = ((HRmax − HRrest) × intensity) + HRrest
Example
HRmax 190, HRrest 60, 70% intensity: target = (130 × 0.7) + 60 = 151 bpm.
Estimate HRmax as about 220 minus your age if you don’t know it.
Important
This tool is for general educational purposes only and is not medical advice, diagnosis, or treatment. It does not replace evaluation by a qualified healthcare professional — consult one for any health decision. Last updated: August 2026.
Frequently Asked Questions
What is the Karvonen formula?
A method to find target heart rate using heart rate reserve — the gap between your max and resting heart rates.
How do I find my max heart rate?
A common estimate is 220 minus your age, though a supervised test is more accurate.
What intensity should I train at?
Often 50-85% of heart rate reserve; pick a zone suited to your goal and fitness, and consult a professional if unsure.