What does .io mean?
Registry operator: Internet Computer Bureau Limited — per the IANA root database.
Source: IANA root zone database, checked August 23, 2026.
What .io is actually used for
io = input/output made this the developer TLD, and that association still pays rent. Two caveats: renewals are 3–5x a .com, and the UK–Mauritius Chagos deal means the 'IO' country code could theoretically be retired someday (precedent says years of transition, but .com never has this conversation). For a dev-facing product it remains a strong, safe-enough pick.
Is .io a country code or generic domain?
.io is technically a country-code TLD (the ccTLD for British Indian Ocean Territory), but it's widely marketed and used as a general-purpose extension. Google treats several such ccTLDs — including this one where applicable — as generic rather than geo-targeted.
Who runs .io?
.io is operated by Internet Computer Bureau Limited, the registry for British Indian Ocean Territory. It has been live in the official IANA DNS root since 1997.
Can anyone register a .io domain?
Yes — .io is open for public registration through accredited registrars. Availability of a specific name still depends on whether someone already owns it, and some ccTLDs add local-presence or ID requirements. Here’s how to check whether a specific name is taken.
Should you use it?
Our short answer: The default startup TLD of the 2010s. Still credible for dev tools, but pricier and no longer novel — and its ccTLD status has a real geopolitical asterisk. For the full pros, cons, and rating, read the complete .io review.