Domain Extractor: A Practical Guide
Use Domain Extractor to obtain the hostname from a URL and remove a leading www. when present. It is useful for a quick hostname check. It does not perform a public-suffix lookup or automatically reduce every subdomain to its registrable domain.
How to Use Domain Extractor
- Enter the web URL.
- Select Analyze.
- Read the returned hostname.
- Check whether a remaining subdomain is relevant to your task.
Hostname Is Not Always the Registrable Domain
A URL such as https://blog.example.co.uk/post contains the hostname blog.example.co.uk. Removing the leading www. does not imply removing blog or determining that example.co.uk is the registered domain.
The extraction does not query DNS, WHOIS, ownership or domain-expiry information. A returned name can be syntactically valid even if it does not resolve or has no website.
Worked Example
https://www.example.com/a returns example.com. https://shop.example.com/a retains shop.example.com.
When grouping traffic by registered organization, you need public-suffix-aware processing rather than assuming the last two labels always identify the registration.
Inspect all address components: use the URL Parser.
Create a preferred-URL declaration: use the Canonical Tag Generator.
Checks and Common Mistakes
- Do not treat a subdomain as automatically independent ownership.
- Check internationalized names carefully.
- Do not interpret output as DNS verification.
- Avoid pasting private URL tokens unnecessarily.
Frequently Asked Questions
Does it remove every subdomain?
No. The current implementation removes a leading www. only.
Does it check expiry or ownership?
No. Those require separate domain-data services.
Can I paste a whole list?
The current field handles one URL; do not assume batch extraction is supported.
Related Tools for the Next Step
- URL Parser: Inspect all address components.
- Canonical Tag Generator: Create a preferred-URL declaration.
- DNS Prefetch Tag Generator: Prepare a hostname hint.
- Preconnect Tag Generator: Prepare an origin connection hint.
Reference
Further reading: MDN URL hostname.