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"\b540[^$](\s+\d{3,})" test_str = ("090323 0014 0006 0 506 120\n" "090323 0020 0008 0 100 506\n" "090323 0121 0001 0 506 540\n" "090323 0851 0002 0 550 315\n" "090323 0858 0004 0 600 540\n" "090323 0900 0009 0 100 170\n" "090323 0906 0002 0 500 530\n" "090323 0912 0005 9 888 6999 989888888888 7 001 0\n" "090323 0913 0006 9 888 140 989888888888 7 001 0\n" "090323 0922 0002 0 550 205\n" "090323 0927 0005 9 888 6999 989888888888 7 001 0\n" "090323 0928 0012 9 888 140 989888888888 7 001 0\n" "090323 0930 0004 0 550 120\n" "090323 0931 0021 9 888 120 989888888888 7 001 0\n" "090323 0937 0023 7 9 888 89888888888 150 7 010 4\n" "090323 0937 0005 9 888 6999 989888888888 7 001 0\n" "090323 0937 0000 0 100 130\n" "090323 0939 0022 9 888 140 989888888888 7 001 0\n" "090323 0939 0002 0 100 602\n" "090323 0942 0013 9 888 120 989888888888 7 001 0\n" "090323 0944 0009 9 888 120 989888888888 7 001 0\n" "090323 0944 0003 9 888 130 989888888888 7 001 0\n" "090323 0952 0007 9 888 6999 989888888888 7 001 0\n" "090323 1002 0041 9 888 120 989888888888 7 001 0\n" "090323 1005 0004 0 506 100\n" "090323 1013 0002 0 100 413\n" "090323 1015 0000 9 888 6999 989888888888 7 001 0\n" "090323 1017 0004 9 888 6999 989888888888 7 001 0\n" "090323 1018 0010 9 888 120 989888888888 7 001 0\n" "090323 1024 0001 0 130 140\n" "090323 1025 0004 0 500 130\n" "090323 1026 0005 0 530 500\n" "090323 1027 0036 7 9 888 89888888888 150 7 012 4\n" "090323 1028 0005 7 9 888 89888888888 150 7 013 4\n" "090323 1030 0019 9 888 120 989888888888 7 001 0\n" "090323 1037 0001 0 540 506\n" "090323 1037 0002 0 600 506\n" "090323 1041 0002 A 9 888 89888888888 173 3 016 4\n" "090323 1043 0052 9 888 120 988128888885 7 001 0\n" "090323 1043 0002 0 600 540\n" "090323 1045 0001 9 888 6999 989888888888 7 001 0\n" "090323 1045 0001 9 888 540 989888888888 7 001 0\n" "090323 1047 0005 7 888 5651 524 7 017 4\n" "090323 1047 0005 9 9 888 888 89888888888 9840 7 001 018 0\n" "090323 1048 0004 0 500 530\n" "090323 1106 0001 0 600 506\n" "090323 1118 0001 9 888 6999 989888888888 7 001 0\n" "090323 1118 0005 9 888 120 989888888888 7 001 0\n" "090323 1123 0003 0 540 506\n" "090323 1126 0001 7 9 888 89888888888 140 7 019 4\n" "090323 1127 0003 9 888 6999 988188888888 7 001 0\n" "090323 1128 0009 9 888 120 988188888888 7 001 0\n" "090323 1135 0003 0 533 100\n" "090323 1144 0004 0 533 100\n" "090323 1145 0000 7 9 888 89888888888 544 7 020 4\n" "090323 1146 0003 0 130 316\n" "090323 1147 0004 9 888 6999 989888888888 7 001 0\n" "090323 1147 0002 9 888 140 989888888888 7 001 0\n" "090323 1148 0002 0 550 120\n" "090323 1149 0007 7 9 888 89888888888 544 7 022 4\n" "090323 1149 0000 7 9 888 89888888888 514 7 023 4\n" "090323 1151 0006 9 888 6999 989888888888 7 001 0\n" "090323 1155 0043 9 888 120 989888888888 7 001 0\n" "090323 1157 0001 9 888 6999 989888888888 7 001 0\n" "090323 1158 0001 0 130 140\n" "090323 1158 0004 9 888 6999 989888888888 7 001 0\n" "090323 1159 0014 9 888 140 989888888888 7 001 0\n" "090323 1202 0005 0 100 314\n" "090323 1214 0002 0 100 310\n" "090323 1218 0005 7 9 888 89888888888 172 3 024 4\n" "090323 1222 0001 0 540 600\n" "090323 1222 0007 7 9 888 89888888888 172 3 025 4\n" "090323 1225 0010 9 888 120 989888888888 7 001 0\n" "090323 1228 0002 0 130 509\n" "090323 1229 0016 9 888 120 989888888888 7 001 0\n" "090323 1234 0003 0 100 544\n" "090323 1241 0015 7 9 888 89888888888 508 7 026 4\n" "090323 1242 0005 9 888 6999 989888888888 7 001 0\n" "090323 1243 0011 9 888 140 989888888888 7 001 0\n" "090323 1245 0018 0 100 208") 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