diff --git a/pydantic/networks.py b/pydantic/networks.py
--- a/pydantic/networks.py
+++ b/pydantic/networks.py
@@ -69,8 +69,8 @@ def url_regex() -> Pattern[str]:
             r'(?:(?P<scheme>[a-z][a-z0-9+\-.]+)://)?'  # scheme https://tools.ietf.org/html/rfc3986#appendix-A
             r'(?:(?P<user>[^\s:/]*)(?::(?P<password>[^\s/]*))?@)?'  # user info
             r'(?:'
-            r'(?P<ipv4>(?:\d{1,3}\.){3}\d{1,3})|'  # ipv4
-            r'(?P<ipv6>\[[A-F0-9]*:[A-F0-9:]+\])|'  # ipv6
+            r'(?P<ipv4>(?:\d{1,3}\.){3}\d{1,3})(?=$|[/:#?])|'  # ipv4
+            r'(?P<ipv6>\[[A-F0-9]*:[A-F0-9:]+\])(?=$|[/:#?])|'  # ipv6
             r'(?P<domain>[^\s/:?#]+)'  # domain, validation occurs later
             r')?'
             r'(?::(?P<port>\d+))?'  # port

Is there any reason that pydantic is not using the [python builtin url parser](https://docs.python.org/3/library/urllib.parse.html)?
`11.11.11.11` looks like an ip address which is what's causing the problem. Happy to accept a PR if you can find an easy way to fix this, but I think it's not trivial.

> Is there any reason that pydantic is not using the [python builtin url parser](https://docs.python.org/3/library/urllib.parse.html)?

Yes,

```py
 from urllib.parse import urlparse
urlparse('not valid')
#> ParseResult(scheme='', netloc='', path='not valid', params='', query='', fragment='')
```
all strings are parsed, it's not trivial to see how you'd use `urlparse` to check if a URL is valid, and then give a reasonable error when it's not.

I guess we could check `scheme` is ok, then check `netloc` is not empty and use regexes to see if it's an IP or a valid domain, and so on. I've no idea if this would be more performant than the current solution.

pydantic's URL parsing using regexes was originally taken from marshmallow, then altered a lot.

I suspect that `urlparse` is not a golden panacea or all other validation libraries would be using it, but maybe I'm wrong.
diff --git a/tests/test_networks.py b/tests/test_networks.py
--- a/tests/test_networks.py
+++ b/tests/test_networks.py
@@ -51,6 +51,8 @@
         AnyUrl('https://example.com', scheme='https', host='example.com'),
         'https://exam_ple.com/',
         'http://twitter.com/@handle/',
+        'http://11.11.11.11.example.com/action',
+        'http://abc.11.11.11.11.example.com/action',
     ],
 )
 def test_any_url_success(value):
@@ -159,6 +161,16 @@ def test_ipv4_port():
     assert url.password is None
 
 
+def test_ipv4_no_port():
+    url = validate_url('ftp://123.45.67.8')
+    assert url.scheme == 'ftp'
+    assert url.host == '123.45.67.8'
+    assert url.host_type == 'ipv4'
+    assert url.port is None
+    assert url.user is None
+    assert url.password is None
+
+
 def test_ipv6_port():
     url = validate_url('wss://[2001:db8::ff00:42]:8329')
     assert url.scheme == 'wss'

Validation Error on HttpUrl and AnyHttpUrl on parsing valid url starting with 4 numbers
# Validation Error on HttpUrl and AnyHttpUrl on parsing valid url starting with 4 numbers

Output of `python -c "import pydantic.utils; print(pydantic.utils.version_info())"`:
```
             pydantic version: 1.5.1
            pydantic compiled: True
                 install path: /opt/virtualenvs/python3/lib/python3.8/site-packages/pydantic
               python version: 3.8.3 (default, May 14 2020, 20:11:43)  [GCC 7.5.0]
                     platform: Linux-5.4.0-1009-gcp-x86_64-with-glibc2.27
     optional deps. installed: []
```

```py
from pydantic import BaseModel, HttpUrl, AnyHttpUrl

class MyModel(BaseModel):
    url: HttpUrl

class MyModel2(BaseModel):
    url: AnyHttpUrl

a = MyModel(url='http://abc.11.11.11.11.nip.io/action')
b = MyModel2(url='http://abc.11.11.11.11.nip.io/action')
c = MyModel(url='http://11.11.11.11.nip.io/action')
d = MyModel2(url='http://11.11.11.11.nip.io/action')
```

Output of `c` and `d`
```
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "pydantic/main.py", line 338, in pydantic.main.BaseModel.__init__
pydantic.error_wrappers.ValidationError: 1 validation error for MyModel2
url
  URL invalid, extra characters found after valid URL: '.nip.io/action' (type=value_error.url.extra; extra=.nip.io/action)
```

`a` and `b` can be validated

`c` and `d` raise ValidationError

However they are valid URL.


tests/test_networks.py::test_any_url_success[http://11.11.11.11.example.com/action]
tests/test_networks.py::test_any_url_success[http://example.org] tests/test_networks.py::test_any_url_success[http://test] tests/test_networks.py::test_any_url_success[http://localhost0] tests/test_networks.py::test_any_url_success[https://example.org/whatever/next/] tests/test_networks.py::test_any_url_success[postgres://user:pass@localhost:5432/app] tests/test_networks.py::test_any_url_success[postgres://just-user@localhost:5432/app] tests/test_networks.py::test_any_url_success[postgresql+psycopg2://postgres:postgres@localhost:5432/hatch] tests/test_networks.py::test_any_url_success[foo-bar://example.org] tests/test_networks.py::test_any_url_success[foo.bar://example.org] tests/test_networks.py::test_any_url_success[foo0bar://example.org] tests/test_networks.py::test_any_url_success[https://example.org] tests/test_networks.py::test_any_url_success[http://localhost1] tests/test_networks.py::test_any_url_success[http://localhost/] tests/test_networks.py::test_any_url_success[http://localhost:8000] tests/test_networks.py::test_any_url_success[http://localhost:8000/] tests/test_networks.py::test_any_url_success[https://foo_bar.example.com/] tests/test_networks.py::test_any_url_success[ftp://example.org] tests/test_networks.py::test_any_url_success[ftps://example.org] tests/test_networks.py::test_any_url_success[http://example.co.jp] tests/test_networks.py::test_any_url_success[http://www.example.com/a%C2%B1b] tests/test_networks.py::test_any_url_success[http://www.example.com/~username/] tests/test_networks.py::test_any_url_success[http://info.example.com?fred] tests/test_networks.py::test_any_url_success[http://info.example.com/?fred] tests/test_networks.py::test_any_url_success[http://xn--mgbh0fb.xn--kgbechtv/] tests/test_networks.py::test_any_url_success[http://example.com/blue/red%3Fand+green] tests/test_networks.py::test_any_url_success[http://www.example.com/?array%5Bkey%5D=value] tests/test_networks.py::test_any_url_success[http://xn--rsum-bpad.example.org/] tests/test_networks.py::test_any_url_success[http://123.45.67.8/] tests/test_networks.py::test_any_url_success[http://123.45.67.8:8329/] tests/test_networks.py::test_any_url_success[http://[2001:db8::ff00:42]:8329] tests/test_networks.py::test_any_url_success[http://[2001::1]:8329] tests/test_networks.py::test_any_url_success[http://[2001:db8::1]/] tests/test_networks.py::test_any_url_success[http://www.example.com:8000/foo] tests/test_networks.py::test_any_url_success[http://www.cwi.nl:80/%7Eguido/Python.html] tests/test_networks.py::test_any_url_success[https://www.python.org/\u043f\u0443\u0442\u044c] tests/test_networks.py::test_any_url_success[http://\u0430\u043d\u0434\u0440\u0435\u0439@example.com] tests/test_networks.py::test_any_url_success[https://example.com] tests/test_networks.py::test_any_url_success[https://exam_ple.com/] tests/test_networks.py::test_any_url_success[http://twitter.com/@handle/] tests/test_networks.py::test_any_url_success[http://abc.11.11.11.11.example.com/action] tests/test_networks.py::test_any_url_invalid[http:///example.com/-value_error.url.host-URL tests/test_networks.py::test_any_url_invalid[https:///example.com/-value_error.url.host-URL tests/test_networks.py::test_any_url_invalid[http://.example.com:8000/foo-value_error.url.host-URL tests/test_networks.py::test_any_url_invalid[https://example.org\\-value_error.url.host-URL tests/test_networks.py::test_any_url_invalid[https://exampl$e.org-value_error.url.host-URL tests/test_networks.py::test_any_url_invalid[http://??-value_error.url.host-URL tests/test_networks.py::test_any_url_invalid[http://.-value_error.url.host-URL tests/test_networks.py::test_any_url_invalid[http://..-value_error.url.host-URL tests/test_networks.py::test_any_url_invalid[https://example.org tests/test_networks.py::test_any_url_invalid[$https://example.org-value_error.url.scheme-invalid tests/test_networks.py::test_any_url_invalid[../icons/logo.gif-value_error.url.scheme-invalid tests/test_networks.py::test_any_url_invalid[abc-value_error.url.scheme-invalid tests/test_networks.py::test_any_url_invalid[..-value_error.url.scheme-invalid tests/test_networks.py::test_any_url_invalid[/-value_error.url.scheme-invalid tests/test_networks.py::test_any_url_invalid[+http://example.com/-value_error.url.scheme-invalid tests/test_networks.py::test_any_url_invalid[ht*tp://example.com/-value_error.url.scheme-invalid tests/test_networks.py::test_any_url_invalid[ tests/test_networks.py::test_any_url_invalid[-value_error.any_str.min_length-ensure tests/test_networks.py::test_any_url_invalid[None-type_error.none.not_allowed-none tests/test_networks.py::test_any_url_invalid[http://2001:db8::ff00:42:8329-value_error.url.extra-URL tests/test_networks.py::test_any_url_invalid[http://[192.168.1.1]:8329-value_error.url.host-URL tests/test_networks.py::test_any_url_invalid[http://example.com:99999-value_error.url.port-URL tests/test_networks.py::test_any_url_parts tests/test_networks.py::test_url_repr tests/test_networks.py::test_ipv4_port tests/test_networks.py::test_ipv4_no_port tests/test_networks.py::test_ipv6_port tests/test_networks.py::test_int_domain tests/test_networks.py::test_co_uk tests/test_networks.py::test_user_no_password tests/test_networks.py::test_user_info_no_user tests/test_networks.py::test_at_in_path tests/test_networks.py::test_fragment_without_query tests/test_networks.py::test_http_url_success[http://example.org] tests/test_networks.py::test_http_url_success[http://example.org/foobar] tests/test_networks.py::test_http_url_success[http://example.org.] tests/test_networks.py::test_http_url_success[http://example.org./foobar] tests/test_networks.py::test_http_url_success[HTTP://EXAMPLE.ORG] tests/test_networks.py::test_http_url_success[https://example.org] tests/test_networks.py::test_http_url_success[https://example.org?a=1&b=2] tests/test_networks.py::test_http_url_success[https://example.org#a=3;b=3] tests/test_networks.py::test_http_url_success[https://foo_bar.example.com/] tests/test_networks.py::test_http_url_success[https://exam_ple.com/] tests/test_networks.py::test_http_url_success[https://example.xn--p1ai] tests/test_networks.py::test_http_url_success[https://example.xn--vermgensberatung-pwb] tests/test_networks.py::test_http_url_success[https://example.xn--zfr164b] tests/test_networks.py::test_http_url_invalid[ftp://example.com/-value_error.url.scheme-URL tests/test_networks.py::test_http_url_invalid[http://foobar/-value_error.url.host-URL tests/test_networks.py::test_http_url_invalid[http://localhost/-value_error.url.host-URL tests/test_networks.py::test_http_url_invalid[https://example.123-value_error.url.host-URL tests/test_networks.py::test_http_url_invalid[https://example.ab123-value_error.url.host-URL tests/test_networks.py::test_http_url_invalid[xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx-value_error.any_str.max_length-ensure tests/test_networks.py::test_coerse_url[ tests/test_networks.py::test_coerse_url[https://www.example.com-https://www.example.com] tests/test_networks.py::test_coerse_url[https://www.\u0430\u0440\u0440\u04cf\u0435.com/-https://www.xn--80ak6aa92e.com/] tests/test_networks.py::test_coerse_url[https://exampl\xa3e.org-https://xn--example-gia.org] tests/test_networks.py::test_coerse_url[https://example.\u73e0\u5b9d-https://example.xn--pbt977c] tests/test_networks.py::test_coerse_url[https://example.verm\xf6gensberatung-https://example.xn--vermgensberatung-pwb] tests/test_networks.py::test_coerse_url[https://example.\u0440\u0444-https://example.xn--p1ai] tests/test_networks.py::test_coerse_url[https://exampl\xa3e.\u73e0\u5b9d-https://xn--example-gia.xn--pbt977c] tests/test_networks.py::test_parses_tld[ tests/test_networks.py::test_parses_tld[https://www.example.com-com] tests/test_networks.py::test_parses_tld[https://www.example.com?param=value-com] tests/test_networks.py::test_parses_tld[https://example.\u73e0\u5b9d-xn--pbt977c] tests/test_networks.py::test_parses_tld[https://exampl\xa3e.\u73e0\u5b9d-xn--pbt977c] tests/test_networks.py::test_parses_tld[https://example.verm\xf6gensberatung-xn--vermgensberatung-pwb] tests/test_networks.py::test_parses_tld[https://example.\u0440\u0444-xn--p1ai] tests/test_networks.py::test_parses_tld[https://example.\u0440\u0444?param=value-xn--p1ai] tests/test_networks.py::test_postgres_dsns tests/test_networks.py::test_redis_dsns tests/test_networks.py::test_custom_schemes tests/test_networks.py::test_build_url[kwargs0-ws://foo@example.net] tests/test_networks.py::test_build_url[kwargs1-ws://foo:x@example.net] tests/test_networks.py::test_build_url[kwargs2-ws://example.net?a=b#c=d] tests/test_networks.py::test_build_url[kwargs3-http://example.net:1234] tests/test_networks.py::test_son tests/test_networks.py::test_address_valid[foobar@example.com-foobar-foobar@example.com] tests/test_networks.py::test_address_valid[s@muelcolvin.com-s-s@muelcolvin.com] tests/test_networks.py::test_address_valid[Samuel tests/test_networks.py::test_address_valid[foobar tests/test_networks.py::test_address_valid[ tests/test_networks.py::test_address_valid[foo.bar@example.com tests/test_networks.py::test_address_valid[foo tests/test_networks.py::test_address_valid[FOO tests/test_networks.py::test_address_valid[<FOOBAR@example.com> tests/test_networks.py::test_address_valid[\xf1o\xf1\xf3@example.com-\xf1o\xf1\xf3-\xf1o\xf1\xf3@example.com] tests/test_networks.py::test_address_valid[\u6211\u8cb7@example.com-\u6211\u8cb7-\u6211\u8cb7@example.com] tests/test_networks.py::test_address_valid[\u7532\u6590\u9ed2\u5ddd\u65e5\u672c@example.com-\u7532\u6590\u9ed2\u5ddd\u65e5\u672c-\u7532\u6590\u9ed2\u5ddd\u65e5\u672c@example.com] tests/test_networks.py::test_address_valid[\u0447\u0435\u0431\u0443\u0440\u0430\u0448\u043a\u0430\u044f\u0449\u0438\u043a-\u0441-\u0430\u043f\u0435\u043b\u044c\u0441\u0438\u043d\u0430\u043c\u0438.\u0440\u0444@example.com-\u0447\u0435\u0431\u0443\u0440\u0430\u0448\u043a\u0430\u044f\u0449\u0438\u043a-\u0441-\u0430\u043f\u0435\u043b\u044c\u0441\u0438\u043d\u0430\u043c\u0438.\u0440\u0444-\u0447\u0435\u0431\u0443\u0440\u0430\u0448\u043a\u0430\u044f\u0449\u0438\u043a-\u0441-\u0430\u043f\u0435\u043b\u044c\u0441\u0438\u043d\u0430\u043c\u0438.\u0440\u0444@example.com] tests/test_networks.py::test_address_valid[\u0909\u0926\u093e\u0939\u0930\u0923.\u092a\u0930\u0940\u0915\u094d\u0937@domain.with.idn.tld-\u0909\u0926\u093e\u0939\u0930\u0923.\u092a\u0930\u0940\u0915\u094d\u0937-\u0909\u0926\u093e\u0939\u0930\u0923.\u092a\u0930\u0940\u0915\u094d\u0937@domain.with.idn.tld] tests/test_networks.py::test_address_valid[foo.bar@example.com-foo.bar-foo.bar@example.com] tests/test_networks.py::test_address_valid[foo.bar@exam-ple.com tests/test_networks.py::test_address_valid[\u03b9\u03c9\u03ac\u03bd\u03bd\u03b7\u03c2@\u03b5\u03b5\u03c4\u03c4.gr-\u03b9\u03c9\u03ac\u03bd\u03bd\u03b7\u03c2-\u03b9\u03c9\u03ac\u03bd\u03bd\u03b7\u03c2@\u03b5\u03b5\u03c4\u03c4.gr] tests/test_networks.py::test_address_invalid[f tests/test_networks.py::test_address_invalid[foo.bar@exam\nple.com tests/test_networks.py::test_address_invalid[foobar] tests/test_networks.py::test_address_invalid[foobar tests/test_networks.py::test_address_invalid[@example.com] tests/test_networks.py::test_address_invalid[foobar@.example.com] tests/test_networks.py::test_address_invalid[foobar@.com] tests/test_networks.py::test_address_invalid[foo tests/test_networks.py::test_address_invalid[foo@bar@example.com] tests/test_networks.py::test_address_invalid[\n@example.com] tests/test_networks.py::test_address_invalid[\r@example.com] tests/test_networks.py::test_address_invalid[\x0c@example.com] tests/test_networks.py::test_address_invalid[ tests/test_networks.py::test_address_invalid[\x1f@example.com] tests/test_networks.py::test_address_invalid["@example.com0] tests/test_networks.py::test_address_invalid["@example.com1] tests/test_networks.py::test_address_invalid[,@example.com] tests/test_networks.py::test_email_str tests/test_networks.py::test_name_email