It offers a straightforward upload process: users can select a file in their browser or send one through an HTTP POST request, including with the command-line tool curl. The service also supports uploads from tools such as ShareX on Windows and Hupl on Android. For greater control over shared links, users can request a longer file ID, retain a sanitized filename in the generated link, or provide a filename when uploading data through a pipe.

Files may be up to 1024 MiB. They are kept for between 3 and 100 days, with retention based on file size: smaller files may remain available longer, while larger files are deleted earlier. The service describes this size-based retention as nonlinear and provides its formula. The software behind x0.at is open source and available on GitHub. Users can contact the service by email to report abuse or make other inquiries. Overall, x0.at focuses on simple, temporary file sharing rather than long-term storage.