From the

FAQ and tutorials:

- What dimensions/units does FEATool use?

FEATool does not use any fixed unit system, it is therefore up to the user define and use consistent units. If for example the geometry length unit is chosen as meters (m), then standard SI-units are recommended for the equation coefficients. Using another length unit such as millimeters (mm) or inches, would require rescaling of the equation coefficients to preserve consistency.