Target Heart Rate (Karvonen) Calculator
The Karvonen method is a refined way to set a training heart rate that accounts for how fit you already are, not just your age. Instead of taking a flat percentage of your maximum heart rate, it works from your heart rate reserve, the gap between your maximum and your resting heart rate. The formula multiplies that reserve by your chosen intensity and then adds your resting heart rate back, producing a target tuned to your individual range. This calculator takes your maximum heart rate, your resting heart rate and a target intensity as a percentage, and returns the heart rate to aim for during exercise. Every figure is computed deterministically from the formula shown below, never estimated, so the worked example reconciles exactly with the result on screen. A common estimate for maximum heart rate is 220 minus your age, though it varies, which is why the field is editable. Moderate activity sits around 50 to 70 percent of reserve and vigorous activity around 70 to 85 percent. Heart rate targets are a guide for healthy adults; medications and conditions can shift them. Anyone with a heart condition, or returning to exercise after a long break, should seek medical advice first.
The Karvonen target is ((max HR - resting HR) x intensity) + resting HR. For a maximum of 190, a resting rate of 60 and an intensity of 70%, the target heart rate is 151 bpm.
Karvonen formula
target HR = ( (max HR - resting HR) x intensity ) + resting HR
max HR = maximum heart rate in bpm
resting HR = resting heart rate in bpm
intensity = fraction of heart rate reserve (0.70 for 70%)
The heart rate reserve is the maximum minus the resting heart rate. Multiplying it by the intensity gives the rise above rest you want, and adding the resting rate back yields the absolute target heart rate.
Worked example
Maximum heart rate 190, resting 60, target intensity 70 percent.
- Heart rate reserve = 190 - 60 = 130
- 130 x 0.70 = 91
- Target = 91 + 60 = 151 bpm
The target heart rate is 151 beats per minute. These are the calculator's default inputs, so the result above matches the widget exactly.
Karvonen target heart rate: frequently asked questions
What is the Karvonen method?
The Karvonen method, also called the heart rate reserve method, sets a training target by accounting for your resting heart rate, not just your maximum. It takes the difference between maximum and resting heart rate, the heart rate reserve, multiplies it by the desired intensity, and adds the resting rate back. This personalizes the target more than a flat percentage of maximum.
What is heart rate reserve?
Heart rate reserve is your maximum heart rate minus your resting heart rate. It represents the range over which your heart rate can rise during exercise. The Karvonen formula expresses training intensity as a percentage of this reserve rather than of the maximum alone, giving a target tuned to your individual fitness.
How do I find my maximum heart rate?
A common estimate is 220 minus your age, though this is only an approximation and varies between people. A graded exercise test supervised by a professional gives a more accurate figure. Because estimates differ, this calculator lets you enter whatever maximum heart rate you choose.
What intensity should I train at?
Moderate-intensity aerobic activity generally corresponds to about 50 to 70 percent of heart rate reserve, and vigorous activity to roughly 70 to 85 percent. The right zone depends on your goals and fitness. Beginners often start lower and build up. Consult a clinician if you have any heart condition.
Is a heart rate target right for everyone?
Heart rate targets are a useful guide for healthy adults, but medications, conditions and individual variation can shift them. Anyone with a cardiovascular condition, or who is starting exercise after a long break, should seek medical advice before training to a heart rate zone.
Official sources
- Physical activity and target heart rate reference: US Centers for Disease Control and Prevention (CDC). As at 25 June 2026.
Reviewed by the CalculatorHub team, edited by James Graham, 25 June 2026. See our methodology. This is general information, not financial, tax, legal or investment advice.