FERMI@Elettra is a new 4th generation synchrotron radiation source currently under construction at the Elettra laboratory, and it is based on a single-pass free electron laser.The toolkit is a rapid application development environment based on Matlab and on the Elegant and Litrack simulation codes. Its purpose is to provide machine physicists and operators with tools for estimating and plotting the main beam parameters of the running accelerator, calculating new settings and corrections, and eventually setting or updating the machine parameters with new calculated values. The toolkit consists of a set of programs and libraries which provide a bridge between the accelerator control system, based on Tango, and the simulation codes. The toolkit also provides the means to perform all the conversions from machine parameters and variables (such as a current circulating in a magnet) to beam dynamics variables (the magnetic field strength, in the example) and vice-versa. The conversion is performed by a set of virtual Tango devices that implement an online magnet model; these devices contain all the needed calibration tables and the logic to read and set the appropriate power supply.