How to use the calculator
- Enter your age to create an estimated maximum of 220 minus age.
- Choose percent of maximum or enter a calm resting value for heart rate reserve.
- Set the lower and upper percentages and save the formula with the BPM result.
Free exercise planning calculator
Target Heart Rate Calculator
Estimate a target heart rate range with percent of maximum heart rate or the heart rate reserve (Karvonen) formula. Change the intensity endpoints, see the arithmetic immediately and keep the selected method beside the result.
Target heart rateEstimated max HRHeart rate reserveCustom intensity range
Start with the default 50–85% age-predicted reference only as general orientation. Do not use a formula to override symptoms, medication guidance, exercise-test results or a clinician-prescribed range.
Interactive estimate
Calculate a target heart rate range
Choose a method, enter your inputs and keep the formula attached to the result.
Estimated target range
90–153 BPM
Estimated maximum: 180 BPM67.5% midpoint: 122 BPM
Target = 180 × intensity
This is a population-based exercise estimate, not a measured maximum, exercise clearance or medical prescription. Medication, health conditions and fitness can change an appropriate target.
Two formulas, two results
Percent of maximum starts at zero. Heart rate reserve starts with the usable span between resting and estimated maximum, then adds resting rate back. The same percentage therefore produces different BPM.
Keep effort in the decision
During moderate activity, the federal talk test says conversation is usually possible but singing is not. During vigorous activity, only a few words may be comfortable before a breath.
What a target heart rate calculation means
A target heart rate is a calculated exercise reference, not a speed limit measured from your body. The most accessible method begins with an age-predicted maximum. The American Heart Association describes the maximum as about 220 − age, with moderate activity around 50–70% and vigorous activity around 70–85% of that estimate. Those figures are population averages. They help translate broad exercise intensity into BPM, but they do not reveal an individual's tested maximum, aerobic threshold, medication response or safe clinical limit.
Keep the method attached to every number. A watch zone based on measured maximum, a laboratory threshold, a percent-of-maximum chart and a heart rate reserve calculation may all show different boundaries. That does not make the arithmetic broken. It means the inputs and definitions differ. Comparing two ranges without their formulas can lead to false precision.
Percent of estimated maximum heart rate
For a 40-year-old, 220 minus 40 gives an estimated maximum of 180 BPM. Fifty percent is 90 BPM, 70% is 126 BPM and 85% is 153 BPM. The general combined reference is therefore 90–153 BPM. The calculation is easy to reproduce because it needs only age, but age cannot describe fitness, exercise mode or individual maximum.
| Step | 40-year-old example | Result |
|---|---|---|
| Estimated maximum | 220 − 40 | 180 BPM |
| 50% point | 180 × 0.50 | 90 BPM |
| 70% point | 180 × 0.70 | 126 BPM |
| 85% point | 180 × 0.85 | 153 BPM |
Do not perform an unsupervised maximal effort merely to replace the estimate. Whether maximal testing is appropriate depends on health, symptoms, training history and the test protocol. If a measured maximum is available from an appropriate supervised test, use the interpretation supplied with that test rather than silently substituting it into a generic online plan.
Heart rate reserve and the Karvonen calculation
Heart rate reserve includes a resting measurement. First subtract resting heart rate from estimated maximum. Then multiply that reserve by the chosen intensity and add resting rate back: target = resting HR + intensity × (maximum HR − resting HR). If the same 40-year-old has a resting rate of 60 BPM, reserve is 120 BPM. The 50% point is 120 BPM, the 70% point is 144 BPM and the 85% point is 162 BPM.
The reserve result is higher than the simple percent-of-maximum result because the calculation begins above the resting baseline. Use a calm, repeatable resting value. A reading after coffee, rushing to the gym or warming up is not a resting input. Do not mix a reserve-based lower boundary with a percent-of-maximum upper boundary; both ends of a range need the same method.
Why your appropriate exercise intensity may differ
Heat, altitude, dehydration, fatigue, stress and caffeine can change heart rate at a familiar workload. Running, cycling and swimming may also produce different responses. Short intervals can finish before heart rate catches up, while a long steady effort may show cardiac drift even when pace or power stays similar. Use the calculation beside the purpose of the session, perceived exertion, breathing, pace or power—not as a command to accelerate whenever BPM is below a boundary.
Beta blockers and other medicines can change maximum and exercise heart rate. Heart conditions, rehabilitation plans and clinician-defined restrictions can make population formulas unsuitable. If any of those apply, ask which method and monitoring equipment you should use. A generic result cannot provide exercise clearance.
Manual checks are delayed after exercise
HeartRateTap estimates BPM from the intervals between taps you make while feeling a pulse. It is not a continuous sensor. After exercise, time passes while you stop safely, find the wrist pulse and begin tapping. The number describes that later tapping window, not the workout peak or average. Use equipment designed for continuous exercise monitoring when the in-session value matters.
If you want to compare a repeatable post-exercise checkpoint, keep the same activity, stop-to-measure delay, posture and method. The separate heart rate recovery calculator can subtract two readings from one documented protocol, but it cannot recreate a value that was not measured.
Related heart rate zone guides
Sources and further reading
We use named, authoritative sources for health reference ranges. The descriptions below explain what each source supports; external sites are responsible for their own content.
- Target Heart Rates Chart — American Heart Association. The age-predicted 220-minus-age estimate and general 50–70% moderate and 70–85% vigorous reference bands.
- Physical Activity Guidelines for Americans, 2nd edition — U.S. Department of Health and Human Services. Relative-intensity context, gradual progression and the talk test for moderate and vigorous activity.
- Tips for Monitoring Aerobic Exercise Intensity — American College of Sports Medicine. Percent-of-maximum and heart-rate-based approaches used alongside perceived exertion.
- Validity of the Maximal Heart Rate Prediction Models among Runners and Cyclists — Journal of Clinical Medicine via PubMed. A large athlete cohort illustrating the individual error in formula-predicted maximum heart rate.
Target heart rate calculator questions
Is 220 minus age my actual maximum heart rate?
No. It is a population estimate used to create a starting reference. An individual's measured maximum can be higher or lower.
What is the heart rate reserve formula?
Heart rate reserve is estimated maximum minus resting heart rate. A target is resting heart rate plus the chosen percentage of that reserve.
Can this calculator prescribe a safe exercise limit?
No. It cannot account for diagnosis, medication, symptoms, a measured exercise test or an individual plan from a qualified professional.