Usability testing is needed to know whether a product can fulfill the desires of its customers or not. A product that has good usability will have good prospects because technically the product is feasible to use. This study aims to test the usability of a new innovative product called GYM ATOM "Gym Machine with Artificial Trainer and Automatic Load Modifier". The three newest features of the gym machine are the gym machine is designed with the all in one concept where 1 machine can not only train 1 muscle but can train 7 different muscles, also having an artificial trainer that allows users to practice even though without a companion trainer, and automatic load modifier which is based on internet of things that use the user's voice input and it is converted into mechanical energy to change the load. Until now, GYM ATOM has been produced and has reached the alpha prototype stage. To reach the beta prototype stage until it can be mass produced, the product needs to be evaluated for its usability. So that the aim of this study is to test the usability level of GYM ATOM with multi-feature testing by using Nielsen’s Heuristics where usability criteria are measured based on the criteria of learnability, efficiency, memorability, errors, and satisfaction. Based on the results of the usability testing, it can be concluded that the total score of usability is 80.667% which is very good usability. But the product still has to be improved because it has a fairly high error percentage on the automatic load modifier feature. This is because the users must use English as their voice input while respondents are Indonesian who are not fluent in English so it is difficult to use if the user is not good at speaking English. As an evaluation, the product needs to be improved by developing its voice input system so that voice input can not only be used with English but also in languages that are in accordance with the capabilities of its users so that it has better usability.