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 specific or extreme cases, they may give results that differ from laboratory measurements.

For the sake of simplicity, only the most basic formulas are explained on the site (example).


The calculators are programmed in JavaScript (running on the workstation), and for the more complex in PHP (running on the site server).

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).

An output value will be replaced by "N/A" (output field), when calculation is "not applicable".

For the power calculators, the VO2max is graphically symbolized by a scale of 5 levels:

Level 1 Evaluation 40 to 50 ml/min/kg
Level 2 Evaluation 50 to 60 ml/min/kg
Level 3 Evaluation 60 to 70 ml/min/kg
Level 4 Evaluation 70 to 80 ml/min/kg (maximum of women)
Level 5 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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