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

Generated Code

import re regex = re.compile(r""" \$ (?=[^$]{3,100}\$) (?<PH>[A-Za-z0-9:_-]{1,20}) (?: (?<C1>\/) (?<RX>(?:[^\\\/\r\n]|\\\/?)*) \/ (?: (?<R>(?:[^\\\/\r\n$]|\\[\/$]?)*) \/ | (?<G>\d*) ) | (?: (?<C2>\() (?<F>(?:[^\t\r\n\f()]|\\[()]?)*) \) )? ) \$ """, flags=re.MULTILINE | re.IGNORECASE | re.VERBOSE) test_str = (" $EX1$ -> EX1\n" " $EX2(a$b$c)$ -> EX2, (, a$b$c\n" " $EX3(abc\\x/)$ -> EX3, (, abc\\x/\n" " $EX4(\\@\\,/&/)$ -> EX4, (, \\@\\,/&/\n" " $EX5/X(Z)Y/$ -> EX5, /, X(Z)Y\n" " $EX6/X(ABC)/1$ -> EX6, /, X(ABC), 1\n" " $EX7/X\\\\Z\\/Y/$ -> EX7, /, X\\\\Z\\/Y\n" " $EX8/(A)/(B)/$ -> EX8, /, (A), (B)\n" " $EX9/(\\\\$A$)\\//(\\\\$B$\\/)/$ -> EX9, /, (\\\\$A$)\\/, (\\\\$B$\\/)\n\n\n" "Lorem Ip$um $EX1$i$ simply dummy $EX1$$EX2(abc)$ te$t of the printing and \n" "type$EX2(abc)$etting indu$try. $EX3(abc\\x/)$ Lorem $EX4(\\@\\,/&/)$Ipsum has been the \n" "industry'$EX5/X(Z)Y/$ standard du$EX6/X(ABC)/1$mmy text $EX7/X\\\\Z\\/Y/$ ever $$$ince the \n" "1500$EX8/(A)/(B)/$, when an $ unknown $EX9/(\\\\$A$)\\//(\\\\$B$\\/)/$ printer took a galley of type ") 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