This study provides the first empirical comparison of communicative practices across public (X), semi-private (Snapchat), and private (WhatsApp) platforms among Saudi Arabian users. It aims to understand how users strategically adapt their linguistic style, resource deployment, and self-presentation to navigate the distinct social norms and technological affordances of each platform. A mixed-methods approach was employed, combining a quantitative online survey with qualitative analysis. The survey captured data from 225 active Saudi social media users on their perceived formality, code-switching frequency, emoji usage, and audience-design strategies. Paired-samples t-tests were used to analyze significant differences in communication across platforms. The findings reveal a clear platform-based hierarchy of communication norms. Formality was highest on the public platform X, moderate on WhatsApp, and lowest on Snapchat. Emoji usage followed an inverse pattern, being most frequent on Snapchat and least frequent on X. These differences were statistically significant (p < .001). In contrast, the frequency of Arabic-English code-switching showed no significant variation across platforms, suggesting it is driven by functional necessity and stable bilingual identity rather than contextual adaptation. Saudi users are sophisticated digital navigators who strategically modulate their communicative practices in response to platform architecture. While pragmatic behaviors like formality and emoji use are highly context-sensitive, core linguistic practices like code-switching remain stable. This study challenges the notion of a monolithic "digital language" and contributes a nuanced model of platform-specific pragmatics, highlighting how cultural values and technological affordances intersect to shape modern social interaction.
