Extract Domains
Paste any text, URLs, or emails and pull out every domain — full hostnames and registrable domains (eTLD+1), validated against the Public Suffix List and deduplicated. Runs in your browser; nothing is uploaded.
About this tool
Extract Domains scans a block of text and pulls out every domain it references — whether it appears as a bare hostname, inside an http/https/ftp URL, or as part of an email address. Choose what you want back:
- Hostnames — the full host as written, e.g.
www.blog.example.co.uk. - Registrable domains — the eTLD+1, e.g.
example.co.uk— the part you could actually register. - Both (default) — both lists, each with a count.
Why the Public Suffix List matters
Naively splitting on dots gets multi-level suffixes wrong: example.co.uk is one
registrable domain, not co.uk. This tool validates every candidate against
Mozilla's Public Suffix List, so it knows that .co.uk, .gov.uk, and
thousands of other suffixes are public — and it correctly drops IP addresses,
version numbers like 3.14, and bogus TLDs.
- Validated: only real, registrable domains survive.
- Deduplicated: the same domain written twice counts once, in first-seen order.
- Private: everything runs locally in your browser via WebAssembly — your text is never uploaded.
Handy for
- Building a clean list of every domain mentioned in an email, log, or document.
- Pulling the apex domains out of a pile of URLs for an allowlist or audit.
- Counting how many distinct organisations a blob of links touches.
FAQ
Why doesn't it extract IP addresses or things like "v1.2.3"?
Every candidate is checked against the Public Suffix List, and only strings whose suffix is a known ICANN or private entry survive. 192.168.0.1 and 3.14 have no real TLD, so they're dropped on purpose — you get domains, not dotted noise. Use an IP-extraction tool for addresses.
What's the difference between "hostname" and "registrable" mode?
Hostname mode returns hosts exactly as written (lowercased), e.g. www.blog.example.co.uk; registrable mode collapses each to its eTLD+1 — example.co.uk, the part you could register. Both (the default) returns the two lists side by side with counts.
In what order are the results returned?
First-seen order by default, which preserves the flow of the source text. Tick Sort to get both lists alphabetically instead. Either way each domain appears once — duplicates are removed after lowercasing and trailing-dot stripping, so Example.COM and example.com. count as one.
Does it find domains inside URLs and email addresses?
Yes — bare hostnames, hosts inside http/https/ftp URLs, and the part after the @ in email addresses are all picked up by the same scan.
Developer & Automation Access
Run it from the terminal
Same engine as this page, headless — via the gizza CLI:
gizza tool extract-domains "Paste text, URLs, or email addresses containing domains…"New to the CLI? Get gizza →
Open it by URL
Pre-fill and auto-run this tool with query parameters — the names match the API/CLI:
https://gizza.ai/tools/extract-domains/?text=Paste%20text%2C%20URLs%2C%20or%20email%20addresses%20containing%20domains%E2%80%A6&mode=both&sort=trueMachine-readable descriptor: tool.json — title + parameters JSON Schema for agents.