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

/
/

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"(.{3})(.{17})(.{17})(.{20})(.{20})(.{10})(.{6})(.{30})(.{8})(.{8})(.{17})(.{3})(.{10})(.{3})(.{10})(.{3})(.{15})(.{15})(.{30})(.{8})(.{17})(.{17})(.{2})(.{1})(.{10})(.{10})(.{10})(.{10})(.{10})(.{15})(.{15})(.{30})(.{30})(.{17})(.{17})(.{35})" test_str = ("PRS00000001 00000999 F9A40A 992419 0000000001 8111437440 201602152016021500000000000000.00 3333333333 b1234567 SNAB111111GCVB2PO34567 0011111 0055555 DEN4444444444 5555555555 REG1111 REG2222 TRANID1 \n" "PRS00000001 00000999 F9A40A 992419 0000000001 8111437440 201602152016021500000000000000.00 3333333333 b1234567 SNBB222222222ZZPO34567 0011111 0055555 DEN4444444444 5555555555 REG1111 REG2222 TRANID2 \n" "PRS00000001 00000999 C7973A 992419 0000000001 8111437440 201602152016021500000000000000.00 3333333333 b1234567 SNCC3WDDDDDD123PO34567 0011111 0055555 DEN4444444444 5555555555 REG1111 REG2222 TRANID3 \n" "PRS00000001 00000999 C7973A 992419 0000000001 8111437440 201602152016021500000000000000.00 3333333333 b1234567 SNDDDDD4R6F1111PO34567 0011111 0055555 DEN4444444444 5555555555 REG1111 REG2222 TRANID4 ") matches = re.search(regex, test_str) if matches: print ("Match was found at {start}-{end}: {match}".format(start = matches.start(), end = matches.end(), match = matches.group())) for groupNum in range(0, len(matches.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = matches.start(groupNum), end = matches.end(groupNum), group = matches.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