# .io domain name checker

.io is the country-code TLD of the British Indian Ocean Territory. Developers adopted it because it reads as "input/output", and it became shorthand for a tech startup. Registration is open to anyone.

Check a name: open https://availablewhois.com/?q=yourname.io (replace `yourname`).

## .io at a glance

- **Type**: Country-code TLD (ccTLD) of British Indian Ocean Territory
- **Best for**: Developer tools, SaaS
- **How we check**: Registry RDAP where the registry publishes it, DNS otherwise. Each result says which one answered.

## Worth knowing

- The UK's 2024 agreement to transfer sovereignty of the Chagos Islands to Mauritius raised questions about .io's long-term future. Nothing has changed for registrants so far, but it's worth watching for a long-lived brand.
- Operated by Identity Digital, which also runs .sh and .ac.
- Usually priced above .com. Check renewal prices before you commit.

## Related TLDs

[`.ai`](https://availablewhois.com/tlds/ai.md) · [`.sh`](https://availablewhois.com/tlds/sh.md) · [`.dev`](https://availablewhois.com/tlds/dev.md) · [`.co`](https://availablewhois.com/tlds/co.md)

Compare them all in the [TLD guide](https://availablewhois.com/tlds.md), or try a [domain hack](https://availablewhois.com/domain-hacks.md) that ends in `.io`.

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Canonical page: https://availablewhois.com/tlds/io · Check a domain: https://availablewhois.com/ · All docs: https://availablewhois.com/llms.txt