SITE.su is an online marketplace specializing in premium domain names, with a catalog of more than 40,000 domains, primarily in the .ru, .su, and .рф zones. The service helps individuals and businesses find memorable, keyword-based names for websites and online projects. Customers can purchase domains online with immediate transfer or rent them by assigning their own DNS servers. Rental options may include a guaranteed right to buy the domain later.

The marketplace provides tools to browse the full catalog, search by keywords or other parameters, and download domain listings in Excel format, including information such as age and ratings. Listings display purchase prices and monthly rental rates, and buyers can add a domain to the appropriate cart for a straightforward transaction. Customers who wish to negotiate can submit a question or price offer through the site; email and phone details are required for inquiries. Help and online chat are available in the support section.