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 single character of: a, b, c or d
    [[ab][cd]]
  • 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]
  • Character class intersection
    [\w&&[^\d]]
  • 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"{\"id\":\"auth_payer_8gtx3241241UH0Y29zP7D931\"}" test_str = "\"\\r\\n```\\n[\\r\\n {\\r\\n \\\"tactic\\\": \\\"targeting\\\",\\r\\n \\\"targeting\\\": \\\"s=1167891 OR s=455871 OR s=455878 OR s=455872 OR s=455873 OR s=455874 OR s=455875 OR s=455876 OR s=455877 OR s=2077 OR s=110598 OR s=261857 OR s=4647 OR s=2042 OR s=2039 OR s=691 OR s=1398 OR s=447247 OR s=428051 OR s=446928 OR s=447359 OR s=225461 OR s=225618 OR s=447527 OR s=447486 OR s=446609 OR s=446767 OR s=447170 OR s=1442 OR s=1421 OR s=3894 OR s=261852 OR s=262377 OR s=633295 OR s=633274 OR s=633286 OR s=633288 OR s=633273 OR s=743155 OR s=743167 OR s=743207 OR s=743149 OR s=743162 OR s=739645\\\"\\r\\n }\\r\\n]\"" 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