.io Domain Guide: Everything You Need to Know About the Tech Startup Extension

The .io domain has become synonymous with tech startups. From GitHub Pages to countless YC-backed companies, .io has cemented itself as the go-to alternative to .com in the tech world. But is it right for your brand?

What Is .io?

.io is the country-code top-level domain for the British Indian Ocean Territory. However, its association with "input/output" in computer science made it attractive to tech companies. Since the early 2010s, it's been widely adopted by startups, developer tools, and SaaS products.

Notable .io users include Repl.it (now Replit), Figma (formerly figma.io), Notion (notion.so but marketed alongside .io), and thousands of developer tools.

Pros of .io Domains

Tech Credibility

In the startup and developer community, .io is a recognized and respected extension. It signals that you're building something technical.

Better Availability

Short, brandable .io names are much easier to find than their .com equivalents. You can still get quality four and five-letter .io domains.

Clean and Memorable

"Yourbrand.io" looks modern and professional. The two-letter extension keeps URLs short.

Developer Appeal

If your target audience is developers or technical users, .io feels native. It's the extension they expect to see.

Cons of .io Domains

Higher Cost

.io domains typically cost $30-60/year, compared to $10-15 for .com. Premium .io names can cost significantly more.

Non-Technical Audiences May Not Recognize It

If your customers aren't tech-savvy, they might not understand or remember .io. They'll try .com instead.

Geopolitical Concerns

The British Indian Ocean Territory's sovereignty is disputed, and there's ongoing discussion about whether .io will continue to exist if the territory's status changes. This is a low-probability but real risk.

Email Deliverability

Some email services have stricter spam filtering for non-.com extensions. While generally not an issue for established domains, it's worth monitoring.

.io Pricing

• Standard registration: $30-60/year
• Premium domains: $100-5,000+/year
• Aftermarket: Quality .io names sell for $1,000-$50,000+

Register through Namecheap, Cloudflare, GoDaddy, or other major registrars. Compare renewal prices — some registrars offer cheap first-year pricing with higher renewals.

.io vs .com

If the .com is available and affordable, get it. The .com is still the default for most internet users. However, if the .com is taken or costs $10,000+:

• .io wins for developer tools, SaaS products, and tech startups
• .com wins for consumer brands, local businesses, and non-tech companies

Many successful companies use .io early on and later acquire the .com as they grow (Figma being a notable example).

SEO Impact

Google treats .io as a generic TLD, not a country-code TLD. This means .io domains aren't geo-restricted and perform the same as .com in search rankings. Your content and backlinks matter far more than your extension.

Best Practices for .io Domains

Register the .com Too (If Possible)

Even if you use .io as your primary domain, owning the .com prevents confusion and competitor exploitation.

Consistent Branding

If you use .io, lean into it. Make ".io" part of your brand identity rather than treating it as a compromise.

Professional Email

Set up proper email on your .io domain with SPF, DKIM, and DMARC records to ensure deliverability.

Watch for Confusion

Monitor the .com version of your domain. If someone else owns it, track what they're doing with it.

Check .io Availability for Your Brand

Ready to see if your brand name is available as a .io domain? Check it alongside other extensions and social media platforms.

Try BrandScout to instantly check your brand name across .io, .com, .ai, and other extensions, plus social media handles. Get the full picture in seconds.