The Supplement 1 to the Guide of the Expression of Uncertainty in Measurement (GUM Suppl. 1) introduces the Monte Carlo Simulation as a method to evaluate the uncertainty of measurement. This talk presents an implementation of the Supplement 1 as Python command line tool called Open Monte Carlo Engine (OMCE). The tool uses an XML formatted input file and calculates a number of simulation runs. The result is written in text file in CSV format. In the first part of the seminar I will discuss the motivation for the development and some details of the implementation. The second part will focus on possible applications of the tool with some life demonstrations. The last part will discuss ongoing and future research which will be performed based on the tool.