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
Processing...

Test String

Code Generator

Language

Generated Code

import re regex = re.compile(r"(?i)(%(25){0,}20|\s)*(%(25){0,}24|\$)(%(25){0,}20|\s)*(%(25){0,}7B|{){0,1}(%(25){0,}20|\s)*(%(25){0,}(6A|4A)|J)(%(25){0,}(6E|4E)|N)(%(25){0,}(64|44)|D)(%(25){0,}(69|49)|I)(%(25){0,}20|\s)*(%(25){0,}3A|:)[\w\%]+(%(25){1,}3A|:)(%(25){1,}2F|\/)[^\n]+", flags=re.MULTILINE) test_str = ("${jndi:ldap://\n" "${jndi:ldaps:/}\n" "${jndi:rmi:/blarg\n" "${jndi:dns://\n" "${jndi:nis://\n" "${jndi:iiop://\n" "${jndi:corba://\n" "${jndi:nds://\n" "${jndi:http://\n" "$jndi:https://\n" " $ { JNDI :ANYPROTOCOL://\n" " $ { JNDI :ANYPROTOCOL://\n" "${jNDi:l%252564ap:/ \n\n" "Breakdown:\n" "(?i) = case-insensitive\n" "(%(25){0,}20|\\s)* = any number of spaces\n" "(%(25){0,}24|\\$) = $\n" "(%(25){0,}20|\\s)*\n" "(%(25){0,}7B|{){0,1} = { zero or one time *Updated condition\n" "(%(25){0,}20|\\s)*\n" "(%(25){0,}(6A|4A)|J) = J\n" "(%(25){0,}(6E|4E)|N) = N\n" "(%(25){0,}(64|44)|D) = D\n" "(%(25){0,}(69|49)|I) =I\n" "(%(25){0,}20|\\s)*\n" "(%(25){0,}3A|:) = :\n" "[\\w\\%]+ = any number of any letters, url encoded or not\n" "(%(25){0,}3A|:)\n" "(%(25){0,}2F|\\/) = /\n" "[^\\n]+ = until end of line\n\n") matches = regex.finditer(test_str) for match_num, match in enumerate(matches, start=1): print(f"Match {match_num} was found at {match.start()}-{match.end()}: {match.group()}") for group_num, group in enumerate(match.groups(), start=1): print(f"Group {group_num} found at {match.start(group_num)}-{match.end(group_num)}: {group}")

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