.io Domain Guide
Everything you need to know about .io domains
What is .io?
.io is the country code top-level domain (ccTLD) for British Indian Ocean Territory. Tech companies repurposed it because "I/O" means input/output in programming. This coincidence made .io the unofficial TLD for tech startups.
The first major companies to use .io did so out of necessity - good .com names were taken. But the pattern stuck. Today, a .io domain signals "we're a tech company" to developers, investors, and technical audiences.
Notable companies using .io include GitHub Pages (github.io), Repl.it, and hundreds of YC-backed startups. The extension has become shorthand for "this is a tech product."
Who Should Use .io?
SaaS companies: .io tells potential customers you're a software product. B2B SaaS companies often find .io performs as well as .com with technical buyers.
Developer tools: APIs, SDKs, and developer platforms fit naturally under .io. Your audience expects tech companies to use tech-signaling domains.
Startups seeking investment: VCs recognize .io as the "startup TLD." It won't hurt your fundraising, and it's often easier to find a memorable .io than .com.
Who should avoid .io: B2C companies targeting non-technical audiences, local businesses, and any company where customers might not know what .io means.
Pricing & Registration
.io domains typically cost $30-60/year through major registrars. Prices vary significantly - Namecheap and Porkbun tend to be cheaper than GoDaddy or Google Domains.
Registration is straightforward with no special requirements. Anyone can register a .io domain. Domains register in 1-year increments and can be renewed for up to 10 years.
Premium .io domains (short words, common terms) can cost thousands. But generic two-word combinations often remain available at standard prices - .io inventory is much better than .com.
How .io Compares
| TLD | Best For | Price Range | Credibility |
|---|---|---|---|
| .io | Tech startups, dev tools | $30-60/year | High (in tech) |
| .com | Everything | $10-15/year | Highest |
| .ai | AI/ML companies | $50-100/year | High (in AI) |
| .dev | Developers, portfolios | $12-20/year | High (in dev) |
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Try DecideDomain FreeFrequently Asked Questions
What does .io stand for?
.io is technically the country code for British Indian Ocean Territory. Tech companies adopted it because "I/O" stands for input/output in programming. The double meaning made it popular with startups, developer tools, and SaaS companies.
Is .io good for SEO?
Google treats .io as a generic TLD, not a country-specific one. This means .io domains can rank globally without geographic restrictions. SEO performance depends on content quality, not the TLD itself.
Why is .io more expensive than .com?
.io costs $30-60/year compared to $10-15 for .com because the registry (Internet Computer Bureau) sets higher wholesale prices. The tech industry's demand for .io domains keeps prices elevated despite better availability than .com.
Should a startup use .io or .com?
Use .com if you can get a good name. If your preferred .com is taken or too expensive, .io signals tech credibility to investors and developers. For B2B tech companies, .io often performs as well as .com for brand recognition.