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Use Register.si’s official .si lookup to check a name and view the registration information that is public. A result showing no registration is only a point-in-time indication: it does not reserve the name. If it is available, complete the registration through a registrar and confirm availability there before ordering.
Check a .si domain name
- Open the Register.si website and enter the complete name, such as
example.si, in its .si domain lookup. - Read the result as current registration information, not a guarantee that the name will remain available or can be registered successfully.
- If the lookup indicates the name is free, proceed through a registrar and check the name again before submitting the registration. Register.si describes registrars as agents between end users and registry operators; the registrar is the channel for registration.
A name cannot already be taken or reserved, and it must satisfy the registry’s naming rules. The lookup does not secure a name for you.
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What “available” means for a .si name
Register.si’s published guidance allows names of 2–63 characters in textual and/or binary representation, subject to its character and format rules. A name must not start or end with a hyphen, and it must not have two consecutive hyphens in the third and fourth positions. The registry also maintains information about allowed characters and reserved names; check those rules if a name is rejected despite appearing unregistered.
Do these 3 things before closing this tab:
1Scan for outdated or missing drivers - takes under a minute2Repair Windows errors before they cause bigger problems3Fix the driver behind crashes, sound loss and screen glitchesAvailability can change between a lookup and an order. A registry result is therefore a useful first check, not a reservation or confirmation of a completed registration.
#1 Best Overall
Find out who holds a registered .si domain
Look up the registered name in Register.si’s public registration-data service. The information shown depends on the holder’s type and the access level of the lookup:
- Legal entity: Register.si says public information includes the holder, technical contact, and registrar.
- Natural person: only the holder’s contact email is public by default. The holder may choose to disclose additional information.
Do not treat an email address or a technical contact as proof of the legal owner. Contact and holder are distinct record fields, and not every lookup displays all fields.
Website lookup or RDAP?
For a one-off check, the Register.si website lookup is the straightforward option. For software or a structured record, Register.si documents an RDAP service—the successor to WHOIS—with JSON results supporting domain, nameserver, and entity objects. The registry’s website and terms also still use the name WHOIS for its lookup service, so both labels may appear.
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Clear out junk files and repair common Windows errorsFree Scan →Scan for outdated or missing drivers - takes under a minuteDriver Scan →Repair Windows errors before they cause bigger problemsFix Now →| Lookup path | Best for | What it provides | Important limit |
|---|---|---|---|
| Register.si website lookup | A one-time human check | A search field and public .si registration information | Results do not reserve a name; visible data varies by holder type and access level. |
| Register.si RDAP service | Technical or machine-readable queries | Structured registration data in JSON | Anonymous users do not see holder or technical-contact details. |
The web lookup and RDAP should not be assumed to expose identical information in every situation. Register.si’s RDAP documentation specifically says anonymous users do not see holder or technical-contact details.
Rank #3
Request information that is not public
If you have a legitimate reason to seek non-public registration data, Register.si accepts a substantiated written request. Explain the legal basis or entitlement so the registry can assess whether disclosure is necessary. Its examples include a trademark owner seeking to exercise rights or a lawyer acting for a client. The registry’s process is not a workaround for privacy limits, and the examples do not establish that general curiosity or unsolicited outreach is sufficient grounds.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.Use registration data responsibly
Register.si’s terms prohibit using lookup data for advertising or targeted marketing, nuisance contact, or copying and publishing the database contents. Treat the information as registration data for appropriate purposes, not as a prospect list.
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