SITE.su is an online marketplace for premium domain names, offering a catalog of more than 40,000 domains across the .ru, .su, and .рф zones. The service is designed for individuals and businesses seeking a suitable web address, with options to purchase a domain or rent it online. Purchases include the immediate transfer of domain administration rights, while rental gives customers the ability to assign their own DNS servers. Rental agreements provide a priority right to buy the domain during the rental term, with the purchase price set in the contract; agreements can last up to 50 months.

Customers can browse the full domain list, download a spreadsheet, or use an advanced search to find names by keywords and other parameters. The marketplace also provides domain details such as price, age, and search-related indicators. For listed domains, visitors can submit questions or propose a price, and assistance is available through the help section and online chat.