Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
Processing...

Test String

Substitution
Processing...

Code Generator

Language

Generated Code

import re regex = re.compile(r"^([^\x00-\x20\x22\x28\x29\x2c\x2e\x3a-\x3c\x3e\x40\x5b-\x5d\x7f-\xff]+|\x22([^\x0d\x22\x5c\x80-\xff]|\x5c[\x00-\x7f])*\x22)(\x2e([^\x00-\x20\x22\x28\x29\x2c\x2e\x3a-\x3c\x3e\x40\x5b-\x5d\x7f-\xff]+|\x22([^\x0d\x22\x5c\x80-\xff]|\x5c[\x00-\x7f])*\x22))*\x40([^\x00-\x20\x22\x28\x29\x2c\x2e\x3a-\x3c\x3e\x40\x5b-\x5d\x7f-\xff]+|\x5b([^\x0d\x5b-\x5d\x80-\xff]|\x5c[\x00-\x7f])*\x5d)(\x2e([^\x00-\x20\x22\x28\x29\x2c\x2e\x3a-\x3c\x3e\x40\x5b-\x5d\x7f-\xff]+|\x5b([^\x0d\x5b-\x5d\x80-\xff]|\x5c[\x00-\x7f])*\x5d))*$", flags=re.MULTILINE) test_str = ("criscrisaaaa@gmail.com.es\n" "mminighin@alpenite.com\n" "!mminighin@alpenite.com\n" "#mminighin@alpenite.com\n" "$mminighin@alpenite.com\n" "%mminighin@alpenite.com\n" "&mminighin@alpenite.com\n" "'mminighin@alpenite.com\n" "*mminighin@alpenite.com\n" "+mminighin@alpenite.com\n" "-mminighin@alpenite.com\n" "/mminighin@alpenite.com\n" "=mminighin@alpenite.com\n" "?mminighin@alpenite.com\n" "^mminighin@alpenite.com\n" "_mminighin@alpenite.com\n" "`mminighin@alpenite.com\n" "{mminighin@alpenite.com\n" "|mminighin@alpenite.com\n" "}mminighin@alpenite.com\n" "~mminighin@alpenite.com\n" "0mminighin@alpenite.com\n" "1mminighin@alpenite.com\n" "2mminighin@alpenite.com\n" "3mminighin@alpenite.com\n" "4mminighin@alpenite.com\n" "5mminighin@alpenite.com\n" "6mminighin@alpenite.com\n" "7mminighin@alpenite.com\n" "8mminighin@alpenite.com\n" "9mminighin@alpenite.com\n" "10mminighin@alpenite.com\n" "prettyandsimple@example.com\n" "very.common@example.com\n" "disposable.style.email.with+symbol@example.com\n" "other.email-with-dash@example.com\n" "fully-qualified-domain@example.com\n" "user.name+tag+sorting@example.com\n" "x@example.com\n" "\"very.(),:;<>[]\\\".VERY.\\\"very@\\\\ \\\"very\\\".unusual\"@strange.example.com\n" "example-indeed@strange-example.com\n" "admin@mailserver1\n" "#!$%&'*+-/=?^_`{}|~@example.org\n" "\"()<>[]:,;@\\\\\\\"!#$%&'-/=?^_`{}| ~.a\"@example.org\n" "example@s.solutions\n" "user@localserver\n" "user@[2001:DB8::1]\n" ".user@[2001:DB8::1]") subst = "" result = regex.sub(subst, test_str) if result: print(result)

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Python, please visit: https://docs.python.org/3/library/re.html