Simu-X is a tool proposed for graphic, real and 3D simulation of the work plan. It allows you to verify, in advance of the execution on the machine, the behaviour of the machine itself during the machining of the workpieces, checking the correct setting of the milling, drilling and cutting operations, as well as checking the collisions with the vices and/or the workpiece. Simu-X allows the simulation of single-workpiece, multi-workpiece and even cutting and separation cycles; it is an essential tool for speeding up the set-up of work cycles. It offers many simple functions such as starting the simulation from the use of a particular tool, stopping and restarting the sequence, increasing the speed of the simulation, and changing the viewing point by the observer. Finally, it shows the indication of the calculation of the working time with a maximum error of 20%, without the need for Time-X.