This study examines the User Experience (UX) of the travel planning website Expedia.com, aiming to evaluate user perceptions of its functionalities. Participants included students from Computer Science and Tourism programs. The experiment was conducted in a usability testing laboratory, utilizing both qualitative and quantitative methodologies to analyze user interactions with the platform. Prior to the experiment, participants completed a questionnaire assessing their familiarity with online travel booking platforms, establishing a baseline of prior knowledge and experience. They were then assigned tasks simulating realistic user behaviors, such as searching for flights, booking accommodations, and comparing travel packages. Upon completing these tasks, a post-experiment survey gathered feedback on their interaction with the website. The study employed the co-discovery method, in which pairs of participants performed tasks collaboratively while verbalizing their thoughts, perceptions, and difficulties. This approach fostered a natural and interactive environment, enabling the identification of usability issues and variations in user interpretation of the platform's functionalities. Data were collected through observations, video recordings, and survey responses. The analysis highlighted that users positively valued the clear organization of the site and the intuitive options for searching accommodations and flights. However, areas for improvement were also identified, particularly concerning interface design elements, such as the lack of clarity in the presentation of details and navigation between tabs, among other aspects requiring adjustments to facilitate a smoother experience. Additionally, it was observed that the Tourist Experience (TX) on the platform is highly subjective, varying according to individual expectations and prior experiences.