Many finite element analysis (FEA) solvers and other engineering software do not check the units of measure provided for their calculations. It is up to the user to ensure the problem is described in a consistent system such that all derived units can be expressed in terms of the base units.
Some inconsistent unit systems will conveniently give good results in a static analysis. However, the results will be nonsensical in a dynamic or transient analysis where the consistent use of time is mandatory.
The correct unit is often unintuitive and mistakes can happen during conversions. This tool performs the dimensional analysis and conversions required to help you define your problem using a consistent system of units.