How the Target Heart Rate Calculator works.
estimated maximum heart rate = 220 − age; moderate = 50–70%; vigorous = 70–85%Age is in whole years and rates are beats per minute. Zone endpoints are rounded to whole beats per minute.
Equation, units, and population
estimated maximum heart rate = 220 − age; moderate = 50–70%; vigorous = 70–85%. Age is in whole years and rates are beats per minute. Zone endpoints are rounded to whole beats per minute. This page names the equation rather than presenting an unexplained score. Check that every value uses the displayed unit and that you belong to the population for which the method is described. The calculation retains full precision internally and rounds only the visible result. A reproducible estimate should let another reader use the same inputs and reach the same arithmetic answer, while still recognizing that mathematical reproducibility does not prove medical suitability.
Worked example
At age 40, estimated maximum heart rate is 180 bpm. The moderate range is about 90–126 bpm and the vigorous range about 126–153 bpm. Work through the example by writing the equation, substituting each labeled input, and preserving units at every step. The example demonstrates arithmetic only; it is not a recommended body measurement, intake, exercise level, laboratory value, or date. Replace every example input with the values from the situation being considered, and retain those inputs with any result you copy. Small differences can arise from rounding, equation versions, atomic-weight conventions, or date boundaries.
What the result means
Zones are general exercise-intensity guides. Talk-test effort, symptoms, clinician guidance, and a measured exercise plan can be more appropriate than a formula. Use the result only for the purpose named on this page and keep the equation, population, and measurement conditions consistent when comparing values over time. If it conflicts with symptoms, a laboratory report, a clinician’s instructions, or a validated measurement, use the appropriate professional evidence rather than this calculator.
Validation and edge cases
Age must be a whole number from 18–100. The tool does not accept a resting rate because it implements the cited simple AHA percentage method rather than the Karvonen formula. Blank, malformed, nonfinite, and out-of-domain inputs fail explicitly without producing NaN or infinity. The bounds prevent obviously implausible values from being mistaken for meaningful answers, but passing a range check does not make an input medically correct. Recheck dates, decimal separators, unit conversions, coefficient choices, and whether a laboratory value uses the expected assay and unit. Contact a qualified professional when a result could affect treatment, medication, pregnancy care, nutrition therapy, or exercise safety.
Limitations and responsible use
The 220-minus-age method is a broad average, not a measured maximum. Fitness, temperature, illness, medicines, pregnancy, disability, and individual response can alter safe intensity. Stop exercise and seek appropriate care for chest pain, faintness, severe breathlessness, or other concerning symptoms. A medical condition or medicine can change a suitable heart rate. FigureNest processes these inputs locally in the browser and does not send them to a calculation service. The page does not create a medical record, assess symptoms, or know personal history. Avoid using estimates to shame a body, pursue unsafe restriction, delay care, determine legal fitness, or replace contraception. Authoritative source links are provided so readers can check the equation version and current guidance before making a consequential decision.
What this tool does not include.
The 220-minus-age method is a broad average, not a measured maximum. Fitness, temperature, illness, medicines, pregnancy, disability, and individual response can alter safe intensity.
Reference guidance and methodology.
Target Heart Rate Calculator questions.
What does the Target Heart Rate Calculator estimate?
Estimate age-based moderate and vigorous exercise heart-rate zones using the American Heart Association’s simple method.
Which equation and units does it use?
estimated maximum heart rate = 220 − age; moderate = 50–70%; vigorous = 70–85%. Age is in whole years and rates are beats per minute. Zone endpoints are rounded to whole beats per minute.
Is this medical advice or a diagnosis?
No. Stop exercise and seek appropriate care for chest pain, faintness, severe breathlessness, or other concerning symptoms. A medical condition or medicine can change a suitable heart rate.
Which limitations matter most for the Target Heart Rate Calculator?
The limits follow from the scope of estimated maximum heart rate = 220 − age; moderate = 50–70%; vigorous = 70–85%; the limitations section explains the relevant population, measurements, and intended use.