SITE.su is an online marketplace specializing in domain names, with more than 40,000 listings across the .ru, .su, and .рф zones. It helps businesses and individuals find memorable, keyword-focused domains for websites, brands, and personal projects. Customers can purchase a domain online, with the site describing the transfer as immediate, or rent one by the month. Rental agreements include a priority right to buy the domain during the rental period, with the purchase price fixed in the contract; agreements can run for up to 50 months. Renting allows customers to assign their own DNS servers.

The marketplace provides domain search by words or themes, an expanded search function, and options to view or download the full catalog, including listings with selected performance metrics. Domain pages show purchase and monthly rental prices, along with information such as registration age and search-related indicators. Customers can submit questions or make an offer, and the site offers help and online chat through its support section.