Short answer: buy the .com if you can afford it. It is the extension people type by default, trust at checkout, and assume when they hear your name. .io remains credible for developer tools, .ai for AI products, and .co as a fallback — but all three leak traffic to the .com equivalent and all three carry weaker resale value.
Why does .com still dominate?
Two reasons, and neither is nostalgia.
The first is default typing behaviour. When someone remembers a brand name but not its extension, they append .com. This is close to automatic. If you own the .io and someone else owns the .com, a meaningful share of people searching for you will land on your competitor — or on a parking page — and never realise their mistake.
The second is trust at the point of transaction. Consumers who are about to enter payment details apply more scrutiny than they do while browsing. An unfamiliar extension introduces a small hesitation at exactly the moment you cannot afford one. For anything consumer-facing with a checkout, this is not a marginal concern.
How the four extensions compare
| .com | .io | .ai | .co | |
|---|---|---|---|---|
| Default typed | Yes | No | No | No |
| Consumer trust | Highest | Low | Moderate | Moderate |
| Developer trust | High | High | High | Moderate |
| Renewal cost | Low | High | Highest | Moderate |
| Resale market | Deep | Moderate | Volatile | Thin |
| Leaks to .com | — | Yes | Yes | Heavily |
| Best for | Anything | Dev tools | AI products | Stopgap |
When is .io actually defensible?
.io earned genuine credibility in developer tooling, open source, and infrastructure. In that specific context it reads as native rather than second-choice, and a technical audience will not blink at it.
The caveats are real, though. Renewal costs run substantially higher than .com and stay high forever. And .io carries geopolitical exposure as a country-code extension, which has produced periodic uncertainty about its long-term administration. For a company planning to exist in twenty years, that is a risk worth pricing.
Is .ai worth the premium?
.ai has been the fastest-moving extension in recent memory, and for AI-native products it does communicate category instantly. If your product genuinely is an AI product, it is a legitimate choice.
Two things to weigh. First, renewal pricing is the highest of any mainstream extension and shows no sign of falling. Second, and more strategically: category-signalling extensions age with the category. A name that reads as current today reads as dated once the category matures and the label stops being a differentiator. Companies that intend to outlive the current AI cycle tend to want a name that does not carry a timestamp.
What about .co?
.co is the weakest of the four for a specific reason: it is one keystroke from .com. That proximity means it does not read as a deliberate choice, it reads as the .com being unavailable — and it loses traffic to the .com constantly, from people who simply typed one letter more.
It works as a genuine stopgap while you raise money to buy the .com. As a permanent home for a brand, it is difficult to recommend.
When a non-.com genuinely makes sense
- Your audience is exclusively technical and will never be confused by .io
- The .com is owned by a large company in an unrelated sector and will never be sold
- You are pre-revenue and need to ship now, with a plan to acquire the .com later
- The .com equivalent is a genuinely worse name — a strong short .io beats a long clumsy .com
At a glance
- .com is the default extension people type when they are unsure
- Non-.com extensions leak traffic permanently to the .com owner
- .io is credible for developer tools but costly and geopolitically exposed
- .ai signals category clearly but ages with the category
- .co is one keystroke from .com — the weakest long-term choice
- A shorter, cleaner .com almost always beats a compromise on extension
Frequently asked questions
Do search engines rank .com higher?
No. Search engines treat mainstream extensions equivalently for ranking. The advantage of .com is behavioural, not algorithmic.
Should I redirect other extensions to my .com?
If you own them, yes — a simple 301 captures the traffic. But buying every extension defensively is rarely the best use of early budget.
Can I start on .io and move to .com later?
Yes, and many companies do. Budget for both the domain purchase and the migration, and expect a temporary ranking dip during the move.
Skip the compromise
Every domain in our collection is a .com — short, brandable, and priced for founders rather than corporations.