Social segregation refers to the degree to which two or more groups are exposed to each other, which has significantly shaped individual lives and contributed to persistent inequalities in societies. This research proposes a conceptualization of individuals' experienced social segregation by moving beyond traditional discussions of residential segregation and delving into the dynamics of daily mobility. The conceptualization involves three key aspects: exposure to diverse environmental/contextual characteristics, interactions with co-present other (groups of) people, and the perceptions of engaging with others. Conducting a comprehensive travel diary survey with GPS tracking, the study targets inhabitants, particularly those with low socioeconomic status and migrants, in Ghent, Belgium, and Tallinn, Estonia. The survey captures travel behavior, daily activities, interactions, and feelings of respondents in various activity spaces. By integrating open-source built environment data and respondents' socioeconomic information, the research aims to analyze the impact of both environmental and individual/household factors on experienced social segregation. Ultimately, this research strives to provide novel insights into social segregation and inform policymakers about potential interventions, including environment and infrastructure improvements, to alleviate social segregation effectively.