Explain it like I'm 12
The target heart-rate calculator estimates maximum heart rate from age, then uses heart-rate reserve to produce a training zone.
Health & Fitness
Max HR / Target Heart Rate Zones Calculator
Estimate maximum heart rate and target training zones using age, resting heart rate and intensity bands.
Calculator
Working calculator
Live result137-161 bpmEstimated max HR 185 bpm; heart-rate reserve 120 bpm; Karvonen zone 60-80%.
Formula used
Estimated max HR = 220 − age. Heart-rate reserve = max HR − resting HR. Target low = reserve × low % + resting HR. Target high = reserve × high % + resting HR.
This is the method behind the answer, so the result can be checked rather than simply trusted.Visual grid
This number is one point on a larger pattern
Max HR / Target Heart Rate Zones is not just a final answer. It is a step on a line: before and after, input and output, assumption and result.
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InputFormulaResult
137-161 bpmCalculationTime keeps the path visible: the input, the method and the final number belong together.
CalculationTime
Max HR / Target Heart Rate Zones Calculation Report
137-161 bpmEstimated max HR 185 bpm; heart-rate reserve 120 bpm; Karvonen zone 60-80%.
Inputs
- Age
- 35 years
- Resting heart rate
- 65 bpm
- Zone low
- 60 %
- Zone high
- 80 %
Method
Estimated max HR = 220 − age. Heart-rate reserve = max HR − resting HR. Target low = reserve × low % + resting HR. Target high = reserve × high % + resting HR.
- At age 35, estimated max HR is 185 bpm. With resting HR 65, a 60-80% reserve zone is about 137-161 bpm.
Assumptions
- Maximum heart rate formulas are approximate.
- Medical conditions, medication and fitness level can change safe training intensity.
- Stop exercise and seek help for chest pain, fainting or severe symptoms.
Notes
Use this space on the printed report for client, supplier, classroom, job-location, measurement, quote or approval notes.
Source references
- CDC Target Heart Rate and Estimated Maximum Heart Rate — public health target heart-rate reference
Formula
Estimated max HR = 220 − age. Heart-rate reserve = max HR − resting HR. Target low = reserve × low % + resting HR. Target high = reserve × high % + resting HR.
Worked example
At age 35, estimated max HR is 185 bpm. With resting HR 65, a 60-80% reserve zone is about 137-161 bpm.
Professional note
Master’s Tip: heart-rate reserve usually gives a more personal zone than simply taking a percent of max heart rate.
Regional and unit assumptions
General fitness estimate using the Karvonen heart-rate-reserve method.
Assumptions and limitations
- Maximum heart rate formulas are approximate.
- Medical conditions, medication and fitness level can change safe training intensity.
- Stop exercise and seek help for chest pain, fainting or severe symptoms.
Methodology & Accuracy
How this calculator is checked
CalculationTime pages are built around visible arithmetic: the formula, assumptions, worked example and practical limitations are shown so the result can be checked rather than simply trusted.
Formula used
Estimated max HR = 220 − age. Heart-rate reserve = max HR − resting HR. Target low = reserve × low % + resting HR. Target high = reserve × high % + resting HR.
Standard or basis
General fitness estimate using the Karvonen heart-rate-reserve method.
Where a calculator follows a named legal, trade or industry standard, that standard is cited visibly. Otherwise the page uses transparent general arithmetic and states its limits.Master's Tip
Master’s Tip: heart-rate reserve usually gives a more personal zone than simply taking a percent of max heart rate.
Related calculators
Questions
Is 220 minus age exact?
No. It is a rough population estimate and individual maximum heart rate can vary.
What is heart-rate reserve?
It is the gap between estimated maximum heart rate and resting heart rate, used to scale training intensity.