SITE.su is an online marketplace for buying and renting domain names, offering a catalogue of more than 40,000 domains, primarily in the .ru, .su and .рф extensions. Its listings include keyword-based names and domains related to different topics, with purchase and monthly rental prices displayed for prospective customers. Buyers can complete a purchase online, with domain administration rights transferred immediately. For rentals, customers can arrange to use their own DNS servers; rental agreements include a priority right to purchase the domain at a price fixed in the contract. The stated maximum rental term is 50 months.

The marketplace provides tools to browse the full domain list, search by keyword or other parameters, and download listings in Excel format. Some entries also display domain age and indicators related to search visibility. Customers can ask questions or make an offer on a particular domain through the site, which directs them to its Help section for contacts and online chat.