Before performing experiments in the lab with dielectrophoresis (DEP), it is useful to predict the particle and cell responses to the electric field. This requires knowledge of particles or cells properties, which can be obtained from the literature, and implementation of equations related to the particle model. MyDEP is a computational software, programmed in Java, aiming to study dielectrophoretic behavior of particles and cells in a suspended medium. More precisely the software can calculate and display the Clausius-Mossotti factor (real and imaginary parts) used in DEP for different conditions (Medium, frequency range, model of particle). It can also calculate the equivalent permittivities and conductivities of particles alone and in suspension in a medium thanks to the Maxwell-Garnett and Asami-Hanaï equations. Graphs representing crossover frequencies vs electrical conductivity of the medium are also available. The program allows the user to specify the electrical as well as the geometrical parameters of the investigated particle. No prior knowledge of the equations behind is required to use the software, which makes it interesting for users non-familiar with DEP. We also provide a database collecting informations from the literature to help the user to start with already existing models. The user can also enrich the database with new information.