Using game elements in a non-game context, called gamification, has grown popular recently and can be seen in education, health, and on e-commerce websites. In this thesis, the use of game elements, specifically badges is evaluated on a secondhand website. The gamification component is implemented in three steps: a paper prototype, a digital prototype, and an implementation in ReactJS. All iterations are iterated using Customer Relationship Management (CRM) with feedback from the client and with Lean UX. The game elements are evaluated using A/B testing and interviews with users from the A- and B tests.  The results show that gamification can have a positive, although small impact on user engagement on a secondhand website. It also shows that gamification can be incorporated to communicate the core values of the business. The A/B test indicated that there is room for improvement in the gamification component, specifically by more clearly showing that badges are clickable and by adding an explanation of how they can be achieved. These improvements would likely contribute to a better user experience and could increase user engagement with the gamification component.