Searching for high efficiency in oil and gas extraction from reservoirs many geologic techniques have been developed to comprehend the characteristics of a reservoir. Many of them are utilized before perforation process, for instance seismic analyses, in which it is possible to estimate the depth, oil-gas ratio and other geological aspects. One known method is the use of propagated waves that are reflected at seabed, another example is the use of pressure and temperature transient during production valves opening and closing during exploratory phase. Using this method, it is possible to estimate the permeability, the different width, the porosity and skin factor. The present study proposes to develop a user-friendly software to determinate the transient pressure and temperature response in a formation test as a function of operation parameters and reservoir characteristics. The software can be expanded in the future to include the solution of the inverse problem.