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

/
/
g

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"(\S| )+\n(\S| )+\n(\S| )+\n((\S| )+|)NSW \d{4}" test_str = ("/////// 4 lines & 3rd line is suburb only\n" "SCIENTIFIC MOTOR BODYWORKS LP\n" "7-9 PERRY STREET\n" "MATRAVILLE\n" "NSW 2036\n" "///////\n" "au\n" "Mascot Auto Repairs\"cod**\n" "155 Coward Street\n" "Mascot NSW 2020\n" "////////////////////////\n" "Mascot Airport Service Station *cod*\n" "Inside Car Wash\n" "237 O'Riordan St\n" "Mascot NSW 2020\n" "////////////////////////maps\n" "7/30-32 Beaconsfield Street\n" "Alexandria NSW 2015\n" "////////////////////////\n" "Pedders Mascot\n" "Unit 1\n" "20 Ricketty Street\n" "Mascot NSW 2020\n" "/////////////////////\n" "Pay Charge\n" "Mr Bump Smash Repair\n" "Unit 12/122 Station Rd\n" "Seven Hills NSW 2147\n" "////////////////////\n" "Pay Charge\n" "Mr Bump Smash Repair\n" "Unit 12 122 Station Rd\n" "Seven Hills NSW 2147\n" "/////// suburb spelling error, character in street line\n" "Woollahra Auto***cod***\n" "120, Oxford St\n" "Woolahra NSW 1350\n" "/// name not complete\n" "North Caringbah Smash Rep\n" "47 Captain Cook Drive\n" "Caringbah NSW 2229\n" "/////\n" "BM Pro Service Centre\n" "Unit8/ 1a Pritchard Plac\n" "Peakhurst NSW 2210 \n" "////\n" "embassy smash repairs\n" "unit 5d 23-25 windsor rd\n" "northmead nsw 2152") matches = re.finditer(regex, test_str) 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