How to use the heart rate zone calculator
Prepare the values for this calculation
Calculate one training-zone range from user-entered resting/max heart rates and intensity percentages using heart-rate reserve. Use the formula below to check that it answers your question. Read the input units before transferring figures from a statement, measurement or dataset.
Enter and check each input
- Resting heart rate (bpm): enter a value at least 1 and no more than 250. Use the unit named in the label or selected above. Do not leave this required field blank.
- Maximum heart rate (bpm): enter a value at least 1 and no more than 260. Use the unit named in the label or selected above. Do not leave this required field blank.
- Lower intensity (%): enter a value at least 0 and no more than 100. Use the unit named in the label or selected above. Do not leave this required field blank.
- Upper intensity (%): enter a value at least 0 and no more than 100. Use the unit named in the label or selected above. Do not leave this required field blank.
The input table gives a complete example. Keep units and time periods consistent across related fields.
Calculate and resolve any input error
Choose Calculate after entering the values. Changes also update the answer after a short pause. If an error appears, follow its message, correct the field and calculate again. Reset restores the example values.
Interpret the answer
Check Target heart-rate zone first. With the unchanged example inputs, it is 138–151 bpm. Interpret it using the formula and assumptions on this page.
Compare and keep a useful result
For a controlled comparison, keep every other example input unchanged and change Resting heart rate (bpm) from 60 to 66. The resulting Target heart-rate zone is 140.4–152.8 bpm. This illustrates the equation’s response to that input, rather than a forecast of real events.
The result diagram shows the inputs, method and output. A numeric chart is shown only when the calculation supports a meaningful numeric relationship.
Use Copy result or Download CSV to keep the answer. Share tool shares the page address without placing your input values in the URL. Recheck inputs and assumptions before using the result for a decision.
Heart Rate Zone Calculator formula
Target HR=HRrest+intensity×(HRmax−HRrest).
Inputs and units
| Input | Format / range | Example |
|---|---|---|
| Resting heart rate (bpm) | minimum 1; maximum 250 | 60 |
| Maximum heart rate (bpm) | minimum 1; maximum 260 | 190 |
| Lower intensity (%) | minimum 0; maximum 100 | 60 |
| Upper intensity (%) | minimum 0; maximum 100 | 70 |
Worked example
Using the example inputs above, the target heart-rate zone is 138–151 bpm.
- Target heart-rate zone
- 138–151 bpm
Results and assumptions
Uses user-entered resting and maximum heart rate; it does not estimate a medically appropriate maximum or prescribe training intensity.
Fix an input or unexpected result
Resting heart rate (bpm) is required. Enter resting heart rate (bpm) using the format and bounds in the input table. Zero and an empty field are different: use zero only if it is allowed and represents your data.
If your answer differs from the example, choose Reset and compare every field, including selected units and options. Check percentage versus decimal entry and whether values describe the same period. Round only the final displayed answer when reproducing the formula.
If a discrepancy remains, report the calculator issue with the page address, non-sensitive example inputs, actual result, expected result and a reference for your calculation.