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 helps businesses and individuals find a memorable web address for a website, online business, or personal project. Customers can browse available names, search by words or other criteria, view a full domain list, or download catalogue data in Excel format.

Domains are available for immediate purchase or rental. A purchase transfers the rights to administer the domain, while rental gives the customer the right to change its name server settings. Rental agreements include a priority right to buy the domain during the rental term, with the purchase price set in the contract; agreements may last up to 50 months. The site supports online transactions and provides contact options, including help and online chat, for questions or price offers. Domain listings may include pricing, age, and search-related rating information to help customers compare options.