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

/
/
gim

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"(?<!x)(?<!\border\s*number\W*)(?=(?:[._ –-]*\d){9})(?!9|66\D*6|00\D*0|(?:\d\D*){3}0\D*0|(?:\d\D*){5}0(?:\D*0){3})\d(?:[._ –-]*\d){4}" test_str = ("x123456789\n" "X123456789\n" "x123-456-789\n" "X123-456-789\n" "123-456-789\n" "ordernumber123-456-789\n" "order number123-456789\n" "order number 123456789\n" "123-456789\n" "123456789\n" "ordernumber-x123456787\n" "ordernumber-123456787\n" "ordernumber - 123456789\n" "ordernumber #123456789\n" "ordernumber *anysplcharacter*123456789\n" "ordernumber !@#$%^&123456789\n" "123456789*@*#123456789\n" "social security number 123-456-789\n" "ordernumber !@#$%^&x123456789\n" "123456789\n" "#@%#$%#$123456789#$%#$^$#\n\n" "123456789\n" "123 45 6789\n" "123-45-6789\n" "123-45-6789\n" "123 – 45 – 6789\n" "123.45.6789\n" "123_45_6789\n" "123 456 789\n" "123-456-789\n" "123 – 456 – 789\n" "123.456.789\n" "123_456_789\n" "1234 56 789\n" "1234-56-789\n" "1234 – 56 – 789\n" "1234.56.789\n" "1234_56_789\n" "12 345 6789\n" "12-345-6789\n" "12 – 345 – 6789\n" "12.345.6789\n" "12_345_6789\n\n" "The number should not be matched at all for the following rules.\n\n" "If the number beginning with the number “9”\n" "912345678\n" "912000000\n\n" "If the number “666” in positions 1 – 3.\n" "666000000\n" "666450000\n" "666129876\n\n" "If the number “000” in positions 1 – 3.\n" "000000000\n" "000450000\n" "000120000\n\n" "If the number “00” in positions 4 – 5.\n" "123006789\n" "876001234\n" "765003456\n\n" "if the number “0000” in positions 6 – 9\n" "123450000\n" "123000000\n" "876000000\n\n" "x123456789\n" "X123456789\n" "x123-456-789\n" "X123-456-789\n\n") matches = re.finditer(regex, test_str, re.IGNORECASE | 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