How to Choose a .si Domain When the .com and .ai Are Taken

AI summary

A .si name makes sense when the .com and the .ai of the same words are already taken or listed for a lot of money. If the .com is free, buy the .com.
Pick plain words or phrases, never one company's brand. Brand look-alikes risk a dispute and are flagged as phishing risks.
Check that people actually search for the words, and that a real business could build on them.
Buy through escrow, keep the holder details accurate, and be realistic: the .si aftermarket is still small.

Why .si is worth a look at all

Since September 2026 the US government calls AI "super intelligence", or SI, and .si, Slovenia's country domain, spells exactly that. It's short, it's open to anyone, and plenty of good words are still cheaper on .si than on .com or .ai.

Be realistic, though. The .si aftermarket has been small. NamePros, analysing NameBio data, counted just over $14,000 in reported .si aftermarket sales in the first half of 2025, and more than 220,000 .si names now exist. A .si only earns its place when the name itself is strong. The four steps below are how to tell.

Step 1: Check the .com and the .ai first

The .com is still the default address people type. If the .com of your words is free, register it and stop there. A .si makes sense when:

the .com is taken, held without a website, or listed for sale at a price you can't justify;
the .ai is taken or listed for a lot too, which is common for any phrase with "AI" in it;
you'd still be proud to put the .si on a business card.

To check, search the name at any registrar. If it's taken, look it up on the big aftermarkets such as Afternic and Spaceship, which show the asking price when an owner has listed it. Remember that an asking price isn't a sale price, but it does tell you the owner won't let it go cheaply.

Step 2: Make sure it isn't someone else's brand

This is where most new .si buyers go wrong. Security firm Netcraft found more than 44,000 .si names that copy an existing .ai name, and it warns that look-alikes are used for phishing. Owning one also invites a dispute: .si disputes are decided under the registry's own rules, published at register.si, and a brand owner can take a copied name away.

A good .si name passes these checks:

It's generic. It describes a category, an activity or an idea, like "web browser" or "EV charging", rather than naming one company or product.
It isn't a registered trademark in your market. Search the free databases: USPTO for the US, EUIPO for the EU and the WIPO Global Brand Database for everywhere else.
No single company is known by it. Search the words on Google. If the first page is one company's site and its social profiles, the name belongs to them in practice, even without a trademark.

Step 3: Prove people use the words

A name is worth more when people already type it. Check three things with any keyword tool (Google Keyword Planner is free with an ads account):

Monthly searches. Phrases with thousands of searches a month are easier to sell and easier to build on.
Cost per click. When advertisers pay several dollars a click, businesses earn money from those visitors, so a buyer can justify the price.
Real buyers. Can you name three kinds of business that would want it? If you can't, a buyer probably won't either.

Step 4: Register or buy it safely

If the name is free, register it at any registrar that sells .si. You don't need to live in Slovenia, and you can register for a single year. The registry requires accurate holder details that match your ID, under the EU's NIS2 rules, so use your real name and address.

If someone already owns it, buy it through escrow, never by sending money directly. On this site every sale runs through Escrow.com: you pay escrow, the domain moves to your registrar account, and only then is the money released.

Two quick examples

Passes: webbrowser.si. The .ai is listed for sale at $48,900, the .com has been held since 2002, it's a plain category name, and 165,000 people search "web browser" every month.
Fails: the .si copy of a well-known chatbot's brand. The .ai is taken, but the name belongs to one company, and owning the copy is a legal and security risk, not an investment.

Names from this store that pass the test

webbrowser.siThe category name for browsers that think and act for you.$5,000 aiprompts.siHome for the words that make models useful.$5,500 aimarket.siThe storefront name for the agent and model economy.$4,500 evcharging.siCharging, routed and priced by smarter software.$4,500 seoservices.siThe two words every business types when it wants to be found on Google.$3,500 enrollments.siAdmissions and sign-ups, handled by an AI that never sleeps.$2,500

Questions

Is a .si domain good for SEO?

.si is a country domain, so Google links it to Slovenia by default. It works well as a brand, a landing page or a short link. If ranking in another country matters most, a .com is still the safer choice.

How much does a .si domain cost?

A new .si costs roughly the same as a normal country domain at most registrars, with no premium renewal. Names already owned by someone cost whatever you agree with the owner.

Can I lose a .si domain I bought?

Yes, if it copies someone's trademark and they win a dispute under the registry's rules, or if you let it expire. Generic names and auto-renew avoid both.

What if the .com is for sale at a fair price?

Then buy the .com. A .si is the smart choice when the .com and .ai are taken or overpriced, not a replacement for a .com you can actually get.

Sources

This post was researched and drafted with AI help from the sources above, then checked by me before publishing. Facts are as reported on the dates shown.