Extend.Domains by Patriali

Highlight a domain anywhere — a tweet, a spreadsheet, a terminal, an email — and Extend.Domains opens a sidebar telling you what it is.

What you get

• Registration — registered or available, creation and expiry dates, registrar, and EPP status codes, read live from the registry's RDAP service.
• DNS — A, NS, and MX records over DNS-over-HTTPS, with parked-domain detection.
• Age — when the Wayback Machine first archived the name.
• Preview — the site's own title, description, and theme colour.
• A local quality score — length, pronounceability, word segmentation, and TLD, with every weight exposed in the options page so you can tune it to your own taste.
• Research links — one click through to Atom, NameBio, DotDB, Ahrefs, WIPO, Trademarkia, TMView and others, scoped to the domain you are looking at.

How it works

Select text and the sidebar updates. Or right-click a selection, press Ctrl+Shift+L (Cmd+Shift+L on Mac), or type a name into the sidebar's search box — "grok" resolves to grok.com. Obfuscated spellings people use to dodge autolinking — example dot com, example[.]com, example • com — resolve too, once you enable that in the options.

On Firefox, host access is requested when you first need it rather than at install, so the DNS and preview blocks will ask for permission the first time. Grant it from the button in the sidebar or from "Site access" in the options page.

What it is not

There is no Extend.Domains server. No account, no sign-up, no API key, no analytics, no telemetry, no remote code. Every lookup goes straight from your browser to the public services that answer it: Cloudflare or Google for DNS, the domain's registry for RDAP, the Internet Archive for age, and the domain's own homepage for its title. Nothing is ever sent to the developer, because there is nowhere to send it.

Affiliate disclosure

When a domain's nameservers show it is listed for sale on Atom.com, the sidebar shows a "Buy now" button whose link carries a referral code — the developer may earn a commission if you buy through it. It is on by default and can be turned off in the options under "Buy now button". No other link in the extension carries a referral code.

Open source (MIT): github.com/patriali/extend.domains