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"[0-9]{4}[A-Z]{4}[0-9]{3}F[0-9]{4}" test_str = ("0209GQQH003F0011SBB FRQ05SUPERB1G 0TR 201509240410 201509240410DEN XDBKR AG99999992EF3B9 F8BB947FECMPTSGGWS G015006 IYYYNEWET 41GBLONN3N5 NY 2PYN 1G 002N YNNNPN0118GQPF000F000100NNNNYNNN0TR 9999999N N 0136GQFR030F0000209GQQH003F0011SBB FRQ05SUPERB1G 0TR 201509240410 201509240410DEN XDBKR AG99999992EF3B9 F8BB947FECMPTSGGWS G015006 IYYYNEWET 41GBLONN3N5 NY 2PYN 1G 002N YNNNPN0118GQPF000F000100NNNNYNNN0TR 9999999N N \n" "0209GQQH003F0011SBB FRQ05SUPERB1G 0TR 201509240410 201509240410DEN XDBKR AG99999992EF3B9 F8BB947FECMPTSGGWS G015006 IYYYNEWET 41GBLONN3N5 NY 2PYN 1G 002N YNNNPN0118GQPF000F000100NNNNYNNN0TR 9999999N N \n" "0209GQQH003F0011SBB FRQ05SUPERB1G 0TR 201509240410 201509240410DEN XDBKR AG99999992EF3B9 F8BB947FECMPTSGGWS G015006 IYYYNEWET 41GBLONN3N5 NY 2PYN 1G 002N YNNNPN0118GQPF000F000100NNNNYNNN0TR 9999999N N ") 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