A small ending. A thoughtful choice.
A practical guide to .si domains.
What is a .si domain? Learn about Slovenia’s domain extension, name rules, availability checks, and what to consider before registering your next project.
What is a .si domain?
.si is the country-code top-level domain for Slovenia. Its registry is operated by ARNES, the Academic and Research Network of Slovenia. That is the official meaning of the extension, as recorded by IANA.
For a maker, those two letters can also be a creative part of a name: a nod to a small idea, a personal project, or superintelligence. Those are branding interpretations, not an official AI designation or an affiliation with an AI company.
Register.si’s registration terms provide for both individuals and organizations as domain holders. You register through a registrar, which handles the application and ongoing management of your domain.
What makes a valid .si name?
Under the registry’s name rules, the part before .si must be between 2 and 63 characters. It cannot start or end with a hyphen. Two hyphens in the third and fourth positions have special restrictions for internationalized names. A name must also use allowed characters and cannot already be taken or reserved.
The registry supports some internationalized names as well as Latin letters, digits, and hyphens. SpinDot keeps its suggestions simple; for a name with accented characters, check the registry’s allowed character list and your chosen registrar’s support.
Choose for the project you want to build
A good shortlist is small enough to compare. Keep a few directions that feel different, then give each name the same practical checks.
- Say it aloud. Could someone spell the full domain after hearing it once? Read the name together with “dot si.”
- Try it in context. Put it in a sentence about your product, a browser tab, and an email address. A clever name still needs to be comfortable to use.
- Leave room to grow. Decide whether the name needs to describe one feature or could cover the next version of your project too.
- Look beyond availability. Check existing products and relevant trademarks before committing. An unregistered domain does not establish rights to a brand name.
Building for an international audience?
Consider the country association as well as the sound. Google uses country-code domains as a geographic signal, and .si is not currently in its list of ccTLDs treated as generic. A short domain ending does not by itself improve search rankings. See Google’s guidance.
Check availability, then the full cost
SpinDot helps you discover ideas and check their registration status. “Looks available” means no registration was found when checked; it is not a reservation or a guarantee that the name can be bought. Confirm the result with the registrar before paying.
Compare the initial registration price with the renewal price, the registration period, and any services bundled with the purchase. Decide whether you need extras such as email or hosting. Use current prices from the registrar rather than treating a promotional price as the ongoing cost.
After registration, the registrar is where you manage renewals and connect the domain to your website. Keep those account details and renewal reminders somewhere you can find again.
Start with a few possibilities
You do not need a finished business plan to start a shortlist. Describe what you’re making, explore a few directions, and save the names you want to revisit. Learn how SpinDot’s wheel and naming assistant work, or jump straight into the studio.
Registry and search guidance checked on October 10, 2026. Refer to the linked official sources for current rules. SpinDot is independent of the .si registry; registration through partner links may earn us a commission at no extra cost to you.