In preliminary stages of ship design, the resistance coefficient is estimated by approximate methods based on system batches or statistically on experimental samples. In the initial phases of the project, we used different methods of predicting the ship’s resistance, which was important to us in hull modeling. The software used to determine resistance is Maxsurf Resistance and Numeca Fine Marine. We used the following methods: – Holtrop and Mennen – The method estimates the resistance of displacement ships. It is based on the model’s resistance statistics and the test drive results. Used to qualitatively and quickly assess ship resistance – Slender Body – . An analytical method suitable for rapid determination of the resistance of the ship, which is based on so- slim or thin body. To calculate total resistance, Maxsurf resistance computes and adds the viscous resistance component by the method of calculating the friction coefficient ITTC’57 and the shape factor being used. The use of CFD simulation was for validation of the previous methods. So in a quick and easy way we have come to the preliminary values of ship resistance. In the pictures below you can see some of our attempts to get certain results.