Design of calculators


The calculators of the site use mathematical models built from reliable scientific information.

They are designed to better estimate a field reality, which means with the lowest possible error margin.

As the formulas are established for the most cases, and not for special or extreme cases, they may sometime give results that do not exactly coincide with others coming from laboratory measures.


The calculators are programmed in JavaScript, and PHP for the more complex. Unlike JavaScript, PHP runs on the server hosting the site.

The units of measurement used are those of the international system (ISO).

An input value will be replaced by "?" (input field), or "0" or grayed (drop-down menu), when it does not allow calculation (under or over sizing, incorrect entry).

For the power calculators, the VO2max level is graphically symbolized by a scale varying from 1 to 5:

Evaluation 40 to 50 ml/min/kg
Evaluation 50 to 60 ml/min/kg
Evaluation 60 to 70 ml/min/kg
Evaluation 70 to 80 ml/min/kg (maximum of women)
Evaluation 80 to 90 ml/min/kg (maximum of men)


The calculators are done to be useful, therefore your comments, suggestions or requests for improvement are welcome.

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