AI summary
- A .si costs about $12 a year on Hostinger, while a .ai costs $90 and needs a two-year commitment.
- The .ai and .com versions of plain AI words often list for tens or hundreds of thousands of dollars, and their .si twins cost far less.
- The biggest .si risk is the word itself, because the SI order mainly covers the US federal executive branch and doesn't bind companies worldwide.
- Most .si names are speculation, so buy one only when the .com and .ai are taken or expensive and the words are generic.
Why AI founders are now weighing .si against .ai
For years the choice for an AI start-up was simple: get the .com if you can, and if you can't, get the .ai. That changed on 29 September 2026, when President Trump signed Executive Order 14434, titled 'Inaugurating the Era of Super Intelligence'. It tells federal agencies to use "Super Intelligence" and "SI" in official communications.
Slovenia's country code is .si, and registrations followed. On 5 October the Register.si counter showed 20,276 new .si names in 24 hours, 46,066 in the past month and 298,682 in total. A registry spokeswoman said August brought fewer than 2,000. From 2023 to 2025, new .si registrations were only dozens a day, according to Adam Cochran.
I've already written about how to pick a .si when the .com and .ai are gone. This guide is a straight comparison of the two extensions on cost, renewal terms, availability of good names and risk.
Cost: about $12 a year against $90 with a two-year commitment
The clearest price comparison I've found comes from The Next Web, which reported that a .si address costs about $12 a year on Hostinger, against $90 for .ai, which needs a two-year commitment. So a new .ai at that registrar means paying for two years up front, while a .si can be bought a year at a time.
The gap keeps growing the longer you hold the name, because the .ai fee is the larger one every single year. For a funded start-up neither number matters much, though. It's the aftermarket price that does the damage, and I'll come to that below.
Renewal terms: what to check before you pay
The one hard difference in the sources is the term: .ai needs a two-year commitment at Hostinger, while .si is priced by the year. Beyond that, I won't guess at renewal rules I can't show you a source for.
My advice is practical. Look at the renewal price on the checkout page, not the first-year offer. Turn on auto-renew. Keep the registrar account under a company email that won't disappear when a co-founder leaves. If you buy a .si on the aftermarket, the same applies: you pay for the name once, then you're paying the renewal fee every year after that.
Availability: where the good names still are
.ai has had years to fill up. Look at the plain AI category words in my own inventory: aiprompts.ai is listed at $44,500, webbrowser.ai at $48,900 and aimarket.ai at $47,995. The .com side is worse. aimarket.com asks $594,888, greatmind.com asks $500,000 and aivideoeditor.com asks $149,995.
.si filled up fast too, but in a different way. Hostinger says .si is now its second most popular extension after .com, yet only about 3% of the names are explicitly about AI. More than half of the .si names bought early through Dynadot went up for resale. Cochran also claimed that before July, "95% of all .si domains had been non-English."
What that means for a founder: the obvious SI words are mostly registered, but there's a lot of resale supply, and much of it sits with resellers rather than builders. Don't pay the first asking price, and don't assume a listed price is a market price.
Risk: what can go wrong with each
The risk with .ai is mostly cost. It's the established choice for AI products, which is exactly why good names are expensive. "For Anguilla, .ai became a second economy. For Slovenia, .si is a nice bonus," Klaudijus Januitis, head of domains at Hostinger, told TechCrunch.
The risk with .si is mostly the word. The order is primarily focused on the executive branch of the US federal government, and it doesn't mean AI companies and researchers around the world must change their terminology, as this explainer points out. Article 3 says SI simply inherits the existing federal definition of AI. If the word doesn't spread beyond Washington, a .si won't read as "super intelligence" to your customers.
There's also political baggage. Cochran claims insiders profited from .si names before the announcement, and Protos reported that one re-listed name, Build.si, is on offer for over $14 million. Gizmodo notes that all the evidence is circumstantial. Still, it's a story your domain could get pulled into.
Two smaller points. Netcraft found 87 .com names pairing well-known brands with the word "superintelligence", offered at $20,000 each, which is a reminder never to buy someone else's brand on any extension. And the registry says it's coping: "Despite the greatly increased number of requests to all Registry systems, all services are operating smoothly," register.si said.
A simple order of checks for an AI start-up
- Check the .com first. If it's free or affordable, buy it. For most readers it's still the better buy.
- Then check the .ai. If it's a fresh registration at about $90 a year, that's cheap enough for an AI product. Take it.
- Only then look at the .si of the same plain words. It makes sense when both twins are taken or listed at five or six figures.
- Skip brand names. A .si copy of one company's brand is a dispute waiting to happen, not an asset.
Should you buy a .si name because of this?
Here's the plain answer. Most .si names are speculation, and the aftermarket for them is small. If you're an AI start-up and the .com or .ai of your words is available at a sensible price, buy that instead. A .si only earns its place when both are taken or expensive and the words are plain, generic ones.
Use the three-question test:
- Are the .com and .ai taken? If either is available at a fair price, buy it instead.
- Is it a generic name and not a brand? Category words are fine. One company's name isn't.
- Do people search for it? If nobody types the phrase, a cheaper extension won't create demand.
A few names in my inventory pass that test on their data. aiprompts.si is $5,500, with 201,000 searches a month and a .ai listed at $44,500. aivideoeditor.si is $5,000, with 201,000 searches a month and a .com asking $149,995. webbrowser.si is $5,000, with 165,000 searches a month and a .ai at $48,900. aimarket.si is $4,500 against a .com at $594,888. greatmind.si is $2,000 against a .com at $500,000. None of that guarantees resale value. It just means the .si is the cheaper way into words people already use. You can see them all at aidomains.si.
Names from this store that pass the test
Questions
How much does a .si cost compared with a .ai?
The Next Web reported that a .si address costs about $12 a year on Hostinger, against $90 for .ai, which needs a two-year commitment.
Does the executive order require companies to use the term SI?
No. The order is primarily focused on the executive branch of the US federal government and doesn't mean AI companies and researchers around the world must change their terminology.
How many .si domains have been registered since the rename?
On 5 October 2026 the Register.si counter showed 20,276 new .si names in 24 hours, 46,066 in the past month and 298,682 in total. A registry spokeswoman said August brought fewer than 2,000.
Are most new .si names about AI?
No. Hostinger said only about 3% of the .si names it sees are explicitly about AI.
Sources
- The Next Web, 2026-10-05
- Gizmodo, 2026-09-30
- Protos, 2026-09-30
- Yahoo, 2026-09-30
- note, 2026-10-16
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.