Why is the result labelled approximate?

Correct splitting needs the full Public Suffix List, which is large and changes regularly. A short built-in list of common suffixes covers most cases and is honest about being a guess.

Domain Parts Parser

Split a hostname into subdomain, registrable domain and suffix.

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About this tool

Splits a hostname into subdomain, registrable domain and public suffix. Nothing is looked up — there is no DNS or WHOIS query behind this, because there is no backend to make one.

Limitations

Uses a bundled subset of the Public Suffix List. Unusual multi-part suffixes may be split incorrectly.
No DNS lookup happens. This is string analysis only.

Questions

Why is the result labelled approximate?: Correct splitting needs the full Public Suffix List, which is large and changes regularly. A short built-in list of common suffixes covers most cases and is honest about being a guess.

Privacy

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