Target Heart Rate Calculator
0-0 bpm target heart rate zone
The Karvonen Method
This calculator uses the Karvonen formula, which factors in your resting heart rate rather than treating everyone at a given age as equally fit. Max heart rate is estimated as 220 minus age, and heart rate reserve (HRR) is max heart rate minus resting heart rate. Your target heart rate at a given intensity is then (HRR × intensity%) + resting heart rate. Because it accounts for cardiovascular fitness through resting heart rate, the Karvonen method generally produces more personalized training zones than the simpler "percentage of max heart rate" approach.
Choosing an Intensity Range
Moderate-intensity activity (roughly 50-70% of heart rate reserve) is the range most health guidelines recommend for general cardiovascular benefit and is sustainable for longer durations. Vigorous intensity (70-85%) builds fitness faster but is harder to sustain and requires a better baseline of conditioning. The default 50-85% range covers both; narrow it to focus on a specific type of workout. For a broader view of your training capacity, pair this with the calories burned calculator to see how intensity affects energy expenditure, or check your BMR to understand your baseline energy needs.
220 Minus Age Is an Estimate
The "220 minus age" formula is a population average with a fairly wide margin of error (plus or minus 10-12 beats per minute for any individual), not a lab-measured value. Actual max heart rate varies with genetics, fitness level, and how it's measured. This tool is an educational estimate, not medical advice — anyone with a heart condition, on medication that affects heart rate, or new to vigorous exercise should get individualized guidance from a doctor before training at high intensities.
Frequently Asked Questions
Why does this calculator ask for my resting heart rate?
It uses the Karvonen method, which factors in heart rate reserve (max heart rate minus resting heart rate) rather than just a flat percentage of max heart rate. This makes the target zone more personalized to your current fitness level than simpler age-only formulas.
What intensity percentage should I use for fat burning versus cardio fitness?
Roughly 50-70% of heart rate reserve is considered moderate intensity, good for sustainable fat-burning workouts and general health, while 70-85% is vigorous intensity that builds cardiovascular fitness faster but is harder to sustain. Beginners typically start at the lower end and work up.