THE .SI FIELD GUIDE
What is a .si domain?
The .si domain country, registry, history and worldwide registration explained.
.si is Slovenia’s country-code top-level domain (ccTLD). IANA lists ARNES as its manager and a registration date of April 1, 1992.
The official country and registry
Register.si is the public-facing .si registry service within ARNES, Slovenia’s academic and research network. A registry maintains the namespace and its rules; a registrar provides the account and registration service you use. This site helps you research the name and provider. It does not operate the .si registry.
Who a .si domain is for
Consider .si for a business serving Slovenia, a project whose brand fits the letters SI, or a short address for a personal site. Registration is open internationally. The domain ending is part of your brand, but a clear product, useful content, and reliable service still do the work of earning trust.
What SI does and does not mean
In technology branding, some people read SI as super intelligence. That interpretation does not change the IANA delegation to Slovenia. A .si domain is not an official certification of artificial intelligence capability, nor a designation issued by the U.S. government.
Start with the exact name
Use the checker to query a .si domain directly against the registry. Read the response as a point-in-time observation. If no record is found, compare providers and check again at checkout. If the name is recorded, inspect its public RDAP data or try an alternative.
.si domain checker
Primary sources
Registry rules come from Register.si. Delegation comes from IANA. Provider details come from the provider. Availability is checked separately and can change at any time.
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