tldextract accurately separates a URL's subdomain, domain, and public suffix, using the Public Suffix List (PSL).

Why? Naive URL parsing like splitting on dots fails for domains like forums.bbc.co.uk (gives "co" instead of "bbc"). tldextract handles the edge cases, so you don't have to.

>>> import tldextract

>>> tldextract.extract('http://forums.news.cnn.com/')
ExtractResult(subdomain='forums.news', domain='cnn', suffix='com', is_private=False)

>>> tldextract.extract('http://forums.bbc.co.uk/')
ExtractResult(subdomain='forums', domain='bbc', suffix='co.uk', is_private=False)

>>> # Access the parts you need
>>> ext = tldextract.extract('http://forums.bbc.co.uk')
>>> ext.domain
'bbc'
>>> ext.top_domain_under_public_suffix
'bbc.co.uk'
>>> ext.fqdn
'forums.bbc.co.uk'

pip install tldextract

no_fetch_extract = tldextract.TLDExtract(suffix_list_urls=())
no_fetch_extract('http://www.google.com')

Via environment variable:

export TLDEXTRACT_CACHE="/path/to/cache"

Or in code:

custom_cache_extract = tldextract.TLDExtract(cache_dir='/path/to/cache/')

Command line:

tldextract --update

Or delete the cache folder:

rm -rf $HOME/.cache/python-tldextract

extract = tldextract.TLDExtract(include_psl_private_domains=True)
extract('waiterrant.blogspot.com')
# ExtractResult(subdomain='', domain='waiterrant', suffix='blogspot.com', is_private=True)

extract = tldextract.TLDExtract(
    suffix_list_urls=["file:///path/to/your/list.dat"],
    cache_dir='/path/to/cache/',
    fallback_to_snapshot=False)

extract = tldextract.TLDExtract(
    suffix_list_urls=["https://myserver.com/suffix-list.dat"])

extract = tldextract.TLDExtract(
    extra_suffixes=["foo", "bar.baz"])

from urllib.parse import urlsplit

split_url = urlsplit("https://example.com:8080/path")
result = tldextract.extract_urllib(split_url)

$ tldextract http://forums.bbc.co.uk
forums bbc co.uk

$ tldextract --update  # Update cached suffix list
$ tldextract --help    # See all options

tldextract uses the Public Suffix List, a community-maintained list of domain suffixes. The PSL contains both:

• Public suffixes: Where anyone can register a domain (.com, .co.uk, .org.kg)
• Private suffixes: Operated by companies for customer subdomains (blogspot.com, github.io)

Web browsers use this same list for security decisions like cookie scoping.

While .com is a top-level domain (TLD), many suffixes like .co.uk are technically second-level. The PSL uses "public suffix" to cover both.

By default, tldextract treats private suffixes as regular domains:

>>> tldextract.extract('waiterrant.blogspot.com')
ExtractResult(subdomain='waiterrant', domain='blogspot', suffix='com', is_private=False)

To treat them as suffixes instead, see How to treat private domains as suffixes.

By default, tldextract fetches the latest Public Suffix List on first use and caches it indefinitely in $HOME/.cache/python-tldextract.

tldextract accepts any string and is very lenient. It prioritizes ease of use over strict validation, extracting domains from any string, even partial URLs or non-URLs.

tldextract doesn't maintain the suffix list. Submit changes to the Public Suffix List.

Meanwhile, use the extra_suffixes parameter, or fork the PSL and pass it to this library with the suffix_list_urls parameter.

Check if it's in the "PRIVATE" section. See How to treat private domains as suffixes.

See URL validation and How to validate URLs before extraction.

1. git clone this repository.
2. Change into the new directory.
3. pip install --upgrade --editable '.[testing]'

tox --parallel       # Test all Python versions
tox -e py311         # Test specific Python version
ruff format .        # Format code

This package started from a StackOverflow answer about regex-based domain extraction. The regex approach fails for many domains, so this library switched to the Public Suffix List for accuracy.