SITE.su is an online marketplace for premium domain names, offering a catalog of more than 39,000 domains in the .ru, .su, and .рф zones. The service helps businesses and individuals find keyword-based domain names for websites and online projects, with search tools for matching terms and more detailed criteria. Visitors can browse the full catalog or download a domain list in Excel format.

Customers can purchase domains online, with administration rights transferred immediately, or rent a domain by assigning their own DNS servers. Rental agreements include a priority right to purchase the domain during the rental period, with the buyout price fixed in the contract. Rental prices are listed per calendar month, and agreements can run for up to 50 months. The marketplace also provides domain details such as age and SEO-related indicators based on Yandex Wordstat and search-engine data. Customers may submit questions or offer a price for a domain, and the site directs users to its Help section for contacts and online chat.