SITE.su is an online marketplace for premium domain names, offering a catalogue of more than 40,000 domains, primarily in the .ru, .su and .рф zones. The service enables customers to purchase a domain outright or rent it, with online transactions designed for immediate processing. A purchase transfers domain administration rights, while rental allows the customer to set their own name servers. Rental agreements include a priority right to buy the domain at a price fixed in the contract and can last up to 50 months.

Customers can browse the full domain list, download catalogue data in Excel, or use extended search to find names by keyword or other criteria. Listings provide information such as purchase and monthly rental prices, domain age and indicators related to search popularity and SEO appeal. Prospective buyers and renters can submit questions or price offers, with contact details and online chat available through the help section.