SITE.su is an online marketplace specializing in premium domain names, with a catalog of approximately 40,000 domains in the .ru, .su, and .рф zones. The service helps businesses and individuals find memorable, keyword-based web addresses for their websites and projects. Customers can purchase a domain online, with administration rights transferred immediately, or rent one by arranging for their own DNS servers to be assigned. Rental agreements include a priority right to buy the domain at a price fixed in the contract; the stated maximum agreement term is 50 months.

The marketplace provides tools to browse the full domain catalog, search by keywords or other parameters, and download a list of available names. Listings show purchase and monthly rental prices, alongside information such as domain age and indicators of search-related appeal. Customers interested in negotiating can submit a question or offer a price, while the site directs users to its Help section for contact details and online chat.