Domains for developers: .dev, .app and .sh
.io gets the attention, but it isn't the only extension that signals 'built by someone technical.' Three others are worth knowing, and two of them carry a rule that surprises people.
Reviewed May 2026
Past .io, there's a small cluster of extensions that read as developer-native. .dev and .app come from Google and behave in a way most domains don't. .sh comes from a tiny island and got adopted for a pun. All three are reasonable picks; the trick is knowing what each one commits you to.
.dev and .app: the HTTPS-only pair
Both .dev and .app are run by Google Registry. .app opened to the public in 2018, .dev in 2019. They share a rule that catches people out: the whole extension is on the HSTS preload list, which means browsers refuse to load any .dev or .app site over plain HTTP. There's no 'continue to insecure site' option. Register one and you need a valid TLS certificate before it works at all.
That sounds like a hurdle and basically isn't, in 2026. Free certificates are everywhere; every serious host issues them automatically. The practical effect is just that you can't stand up a quick HTTP-only page. For a developer audience that's a non-issue (you were going to use HTTPS anyway), and it means a .dev or .app site is encrypted by definition, which is a small, genuine nicety. .dev reads well for developer tools, docs and personal sites; .app for anything app-shaped and consumer-facing.
.sh: the shell domain
.sh is the country-code domain for Saint Helena, a British island in the South Atlantic so remote it only got an airport a few years ago. Developers didn't pick it for the island. They picked it because 'sh' is the Unix shell, so a .sh domain reads as command-line, terminal, scripting. It's a favourite for CLI tools and developer utilities. Unlike .dev and .app there's no HTTPS mandate; it's an ordinary country-code domain that happens to spell something good.
Which one to reach for
None of these is cheap; they all cost more than a .com, the usual story for extensions with a specific audience. Beyond price, pick by what the name is for. Building a tool other developers will use? .dev or .sh both fit, .sh with a little more personality. Shipping an app with a normal-person audience? .app, and the forced HTTPS does quiet work for trust. Want the broadest possible reach, and the name exists on .com? Take the .com; these extensions earn their keep with a technical audience and spend it with everyone else.