SITE.su is an online marketplace specializing in premium domain names, with more than 40,000 domains offered across the .ru, .su and .рф zones. Customers can browse available names, search by keywords and other criteria, and review information such as domain age and search-related indicators. The catalog includes domains in Latin and Cyrillic scripts, with options grouped by matching terms, transliterations, synonyms and translations.

The marketplace supports both immediate purchase and monthly rental. A purchase transfers domain administration rights online, while a rental allows the customer to assign their own DNS servers. Rental agreements include a priority right to buy the domain during the rental period, with the purchase price fixed in the contract; agreements can last up to 50 months. Customers can place orders through the site, submit questions or price offers, and access assistance through the Help section and online chat. The service also provides full catalog downloads, including spreadsheet exports, to help users explore and compare domain options.