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"^((\*)(\/([0-5]?[0-9]))?|(([0-5]?[0-9])(\/([0-5]?[0-9]))?(-([0-5]?[0-9]))?(,([0-5]?[0-9]))*))$", flags=re.MULTILINE | re.DOTALL) test_str = ("*\n" "0\n" "1\n" "2\n" "3\n" "4\n" "5\n" "6\n" "7\n" "8\n" "9\n" "10\n" "11\n" "12\n" "13\n" "14\n" "15\n" "16\n" "17\n" "18\n" "19\n" "20\n" "21\n" "22\n" "23\n" "24\n" "25\n" "26\n" "27\n" "28\n" "29\n" "30\n" "31\n" "32\n" "33\n" "34\n" "35\n" "36\n" "37\n" "38\n" "39\n" "40\n" "41\n" "42\n" "43\n" "44\n" "45\n" "46\n" "47\n" "48\n" "49\n" "50\n" "51\n" "52\n" "53\n" "54\n" "55\n" "56\n" "57\n" "58\n" "59\n" "60\n" "61\n" "*/3\n" "*/3/3\n" "62\n" "63\n" "64\n" "65\n" "0/5\n" "0/5/2\n" "14,18\n" "14,18,14,18,14,18\n" "3-39\n" "3-39-50\n" "14,18,3-39,52") 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