SITE.su is an online marketplace specializing in premium domain names, with more than 40,000 domains available across the .ru, .su, and .рф zones. The service offers both immediate domain purchases and rentals, helping individuals and businesses find names suited to their online projects. A purchase transfers the rights to administer the domain, while rental allows customers to use it by assigning their own name servers. Rental agreements include a priority right to buy the domain during the rental period, with the purchase price fixed in the contract; agreements may run for up to 50 months.

Customers can browse the full domain catalogue, download a list for review, or use advanced search to find names by specific criteria. Listings may include pricing, domain age, and SEO-related indicators. For a listed domain, visitors can submit a question or propose a price, and the site provides help and online chat through its support section. SITE.su also supports account registration and online transactions, including instant transfer following a purchase.