SITE.su is an online marketplace for premium domain names, offering a catalog of around 40,000 domains, primarily in the .ru, .su, and .рф zones. The service enables customers to purchase a domain or rent it by the month, with options to browse listings, search by keywords or other parameters, and download the full domain list. Available names include keyword domains and domains with transliterations or translations.

Purchases are completed online, with domain administration rights transferred to the buyer. For rentals, customers can 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 agreement; contracts may last up to 50 months. The site also provides listing details such as purchase and monthly rental prices, domain age, and search-related indicators. Customers can ask questions or propose a price through the site, and can contact the marketplace through its help section, which offers online chat.