The last international recommended procedures and normatives provide detailed guidelines and formulation for the execution of speed and power sea trials and the analysis of the results. For this reason it starts to be necessary to analyze the data directly onboard as the trials are completed and define the effective contractual speed and power condition of the ship. CETENA recently improved its technical equipment for sea trials measurements, including the custom software “SPEED” aimed to be directly connected with the acquisition one and provide ship performance analysis consistent with both ITTC and ISO normative. In order to guarantee high accuracy in measurement and analysis, each instrument (torquemeter, anemometer, flowmeter, gyro, etc) has been calibrated and certified by accreditated laboratories. The analysis software “SPEED” has been certified by the rules ABS and RINA. The ship speed and power performance analysed by SPEED and thus referred to ideal condition - i.e. with no waves, no wind and prescribed load condition - can be used for verifying the Energy Efficiency Design Index (EEDI) of the ship.