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
No Match

/
/
gm

Test String

Code Generator

Language

Generated Code

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r"(\n|\s)(?:(?:\+?(\d{1}|\d{2}|\d{3})\s*)\s*(?:\(\s*(\d{1}|\d{2}|\d{3})\s*\)|(\d{1,3}))\s*\-?(?:\(\s*(\d{1,3})\s*\)|(\d{3}))\s*\-?(?:\d{2}\s*\-?\d{2}))" test_str = ("\n" "+79996364778 rus\n" "8 (918) 373-6633 rus\n" "+1 650-798-2800 usa \n" " 8(949)373-66-55 rus\n" " +7 (961) 859-56-19 rus\n" "+1 205-635-1136 usa\n" "+22(909)333 4334\n" "+7(985)5310868\n" "+79855310868\n" "88008454545\n" "+55 11 99999-5555 Brazil\n" "+593 7 282-3889 Ecuador\n" "(+44) 0848 9123 456 UK\n" "+1 284 852 5500 BVI\n\n" "+1 345 9490088 Grand Cayman\n" "+32 2 702-9200 Belgium\n" "+65 6511 9266 Asia Pacific\n" "+86 21 2230 1000 Shanghai\n" "+9124 4723300 India\n" "+821012345678 South Korea\n" "And for your extension pleasure\n" "+55 11 99999-5555 ramal 123 Brazil\n" "+55 11 99999-5555 foo786544 Brazil\n\n" "(?!\\b(0)\\1+\\b)(\\+?\\d{1,3})\\s?\\(?\\d{3}\\)?\\s?([. -]?)\\d{3}\\3\\d{4}") matches = re.finditer(regex, test_str, re.MULTILINE) for matchNum, match in enumerate(matches, start=1): print ("Match {matchNum} was found at {start}-{end}: {match}".format(matchNum = matchNum, start = match.start(), end = match.end(), match = match.group())) for groupNum in range(0, len(match.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = match.start(groupNum), end = match.end(groupNum), group = match.group(groupNum))) # Note: for Python 2.7 compatibility, use ur"" to prefix the regex and u"" to prefix the test string and substitution.

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