SITE.su is an online marketplace specializing in premium domain names, with more than 40,000 listings across the .ru, .su, and .рф domain zones. The service helps businesses, organizations, and individuals find memorable keyword-based domains for websites and online projects. Customers can purchase a domain online for immediate transfer or rent one by assigning their own DNS servers. Rental options include a guaranteed right to buy, and visitors can submit a question or offer a price when they wish to negotiate.

The marketplace provides domain search tools, including searches by keywords, translations, and related terms, as well as an advanced search for filtering listings. Users can browse the full catalog online or download a spreadsheet of available domains, with some listings displaying age, ratings, and search statistics. The site also offers account registration and sign-in, a help section, and contact options that include online chat. Prices for individual domains are shown for both purchase and monthly rental, making it easier for prospective buyers and renters to compare options and choose an address suited to their project.