Domain Extractor

What does this Domain Extractor do?

This free online domain extractor scans any block of text and pulls out every domain name it finds. Paste a list of URLs, a batch of email addresses, a log file, or even plain prose that mentions websites — the tool parses it all and returns a clean, deduplicated list of domains.

Unlike simple regex-based extractors that get confused by paths, query strings, and subdomains, this tool normalises everything. It strips the https:// protocol, removes the www. prefix (optionally), and separates the domain from any path or query string. It also detects email addresses and extracts just the domain part after the @ symbol.

Everything runs locally in your browser using JavaScript. Your text never leaves your device — there is no server processing, no logging, and no data storage. Close the tab and it's gone.

How to extract domain names from text

1. Paste your text: Drop URLs, email addresses, or any text containing domains into the input box. You can paste multiple lines at once.
2. Choose your options: Enable Include subdomains to keep blog.example.com as-is, or turn it off to strip down to example.com. Toggle Strip www prefix to drop the leading www.. Enable Extract from emails to pull domains from user@example.com.
3. Click Extract Domains: The tool scans your text, normalises every match, and displays the results in the output panel.
4. Filter and refine: Use the TLD filter chips to show only .com, .org, .io, or any other extension. Toggle Sort to arrange the list alphabetically.
5. Copy or download: Use the Copy List button to grab all domains, or download as a .txt file with one domain per line.

Tip: The tool automatically deduplicates results by default. If you want to see every occurrence (including repeats), just toggle off Remove duplicates.

Why use this Domain Extractor?

Domain vs URL vs Hostname vs Subdomain — what's the difference?

These four terms are often used interchangeably, but they mean different things. Understanding the difference helps you pick the right option when extracting domains.

When you toggle Include subdomains off, this tool converts a hostname like blog.example.com into the registrable domain example.com. That's exactly what you want when you're grouping links by the site they point to, rather than by the specific subdomain.

Understanding TLDs: single-label, multi-part, and new gTLDs

Every domain ends in a top-level domain (TLD). Modern TLDs fall into three buckets, and this tool handles all three:

• Country-code TLDs (ccTLDs): Two-letter codes like .uk, .de, .in, .jp. Some countries use a two-part structure where the registrable domain is example.co.uk rather than co.uk.
• Generic TLDs (gTLDs): Legacy extensions like .com, .org, .net, .info, plus new ones like .app, .dev, .io, .ai, .xyz.
• Multi-part public suffixes: Combinations like .co.uk, .com.au, .co.in, .com.br, .co.jp. These are treated as a single suffix when finding the registrable domain.

Because the tool keeps a curated list of both single-label and multi-part suffixes, it correctly identifies shop.example.co.uk as a subdomain of example.co.uk — not of co.uk. That distinction matters when you're building blocklists, allowlists, or backlink reports.

When would you need to extract domains?

SEO and link analysis

• Extract all external domains linked from a webpage or HTML source
• Build a list of referring domains from backlink reports
• Audit competitor outbound links to understand their link-building strategy
• Identify which third-party services, CDNs, and analytics providers a site uses
• Find broken outbound links by comparing live domains against a crawl log

Cybersecurity and threat intelligence

• Scan log files and incident reports for suspicious or unexpected domains
• Extract domains from phishing email HTML for investigation
• Build allowlists and blocklists from network traffic logs
• Map attack surface by finding all subdomains mentioned in a system
• Compare IOC feeds and deduplicate overlapping domain entries

Email list management

• Extract unique domains from a list of email addresses to segment contacts
• Identify business vs. personal email domains for marketing campaigns
• Clean up messy contact lists by pulling out the domain column
• Find common email providers in a customer database
• Detect disposable email domains before running a campaign

Data cleaning and research

• Extract domains from research papers, articles, or scraped web content
• Clean up URL fields in a spreadsheet by pulling out just the domain
• Build a source list from citations and references
• Normalise inconsistent URL formats in a dataset
• Prepare domain lists for DNS lookups, WHOIS queries, or bulk uptime checks

How domain extraction works under the hood

Domain extraction is more nuanced than running a single regex over text. Here's what the tool actually does:

1. Email detection: When Extract from emails is enabled, the tool scans for email addresses like user@domain.com, extracts the domain part, and marks the matched region as consumed so it won't be double-counted.
2. Full URL detection: It matches complete URLs including the protocol, hostname, port, path, query string, and fragment. The hostname is captured and the entire URL is consumed — so a domain-looking string inside a path like https://example.com/blog/foo.com won't be mistakenly extracted.
3. Bare domain detection: Finally, it scans for plain domains like example.com or sub.domain.co.uk that appear without a protocol. Any match that overlaps an email or URL — or is immediately preceded by @ — is skipped.
4. Normalisation: Each match is cleaned — the protocol is stripped, the path and query string are removed, and the port number is discarded. If Strip www prefix is enabled, the leading www. is removed.
5. Subdomain handling: If Include subdomains is disabled, the tool strips subdomains and keeps only the registrable domain (e.g., blog.example.com → example.com).
6. Strict TLD validation: Each candidate is checked against a curated list of single-label and multi-part TLDs. This filters out false positives like file.txt, example.local, version strings, and IP addresses.
7. Deduplication and sorting: If enabled, duplicates are removed and the list is sorted alphabetically before display.

The tool handles common TLDs including multi-part extensions like .co.uk, .com.au, and .co.in. It also filters out IP addresses, which are not domains.

Best practices for domain extraction

• Paste the raw text. Don't worry about formatting — the tool handles line breaks, commas, tabs, and spaces as separators.
• Toggle subdomains based on your goal. If you're building a blocklist, keep subdomains. If you're doing domain-level analysis, strip them.
• Use Strip www prefix to normalise results when you don't care about the www variant. This is especially useful when comparing two lists for overlap.
• Disable email extraction if you're only interested in URLs. This prevents email domains from polluting your list.
• Use the TLD filter chips to focus on specific extensions. For example, click .io to see only startup domains, or .gov to isolate public-sector sites.
• Sort alphabetically before exporting to make the list easier to scan and deduplicate manually.
• Check the total count. If the "Total Found" number is much higher than "Unique", your input has a lot of repeated domains — dedupe is working.
• Cross-check before acting. Regex-based extraction is very accurate, but always eyeball the results before feeding them into an automation pipeline.

Privacy, accuracy, and limits

Privacy: Nothing you paste into this domain extractor is sent to a server. The extraction engine is a JavaScript function that runs entirely in your browser tab. There is no upload, no queue, no analytics event that includes your text, and no server-side log.

Accuracy: The extractor uses a curated list of single-label and multi-part TLDs to filter out false positives like filenames (style.css) and version strings (1.2.3). It also skips IP addresses, which are valid hosts but not domains. That said, no regex-based extractor is perfect — if you find an edge case, the results are still editable, so you can clean them up before copying or downloading.

Limits: There is no hard limit on input size. Because everything happens in-browser, the practical limit is your device's memory. Lists of tens of thousands of URLs process in under a second on a modern browser. Very large pastes (1 MB+) may take a moment.

Glossary of domain terms

Domain

The human-readable name of a website, made of a second-level label plus a TLD, like example.com.

Subdomain

A prefix added to a domain to create a separate section of a site, like blog in blog.example.com.

Hostname

The full name of a machine on the internet. May include a subdomain and always includes a domain. Example: api.example.com.

TLD

Top-Level Domain — the rightmost label of a domain, such as .com, .org, or .uk.

ccTLD

Country-code TLD — a two-letter code reserved for a country, such as .de for Germany.

gTLD

Generic TLD — extensions not tied to a country, like .com, .org, .app, and .dev.

Public suffix

A suffix under which users can register names. Examples: com, co.uk, github.io.

Registrable domain

The part of a hostname that you actually register — the public suffix plus one label. For blog.example.co.uk, the registrable domain is example.co.uk.

URL

The full web address including protocol, hostname, path, and query string. Example: https://example.com/path?q=1.

Protocol

The scheme at the start of a URL, like https:// or ftp://.

Frequently asked questions