SITE.su is an online marketplace for premium domain names, offering more than 40,000 domains primarily in the .ru, .su, and .рф zones. The service helps businesses and individuals find keyword-based web addresses for online projects, brands, or personal use. Visitors can browse available names, search by keywords or other parameters, and review listings that include purchase and monthly rental prices, along with domain age and search-related indicators.

Customers can buy a domain online, with the marketplace describing the transfer as immediate, or rent one by assigning their own DNS servers. Rental agreements include a priority right to purchase the domain during the rental period, with the buyout price fixed in the agreement; contracts can last up to 50 months. The site also provides options to download the complete domain list, submit an offer, or ask a question about a specific name. Help, contact details, and online chat are available through its support section.