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"^Item([1-9]|[1-4][0-9]|50)$", flags=re.MULTILINE) test_str = ("Winst\n" "Item1\n" "Item2\n" "Item3\n" "Item4\n" "Item5\n" "Item6\n" "Item7\n" "Item8\n" "Item9\n" "Item10\n" "Item11\n" "Item12\n" "Item13\n" "Item14\n" "Item15\n" "Item16\n" "Item17\n" "Item18\n" "Item19\n" "Item20\n" "Item21\n" "Item22\n" "Item23\n" "Item24\n" "Item25\n" "Item26\n" "Item27\n" "Item28\n" "Item29\n" "Item30\n" "Item31\n" "Item32\n" "Item33\n" "Item34\n" "Item35\n" "Item36\n" "Item37\n" "Item38\n" "Item39\n" "Item40\n" "Item41\n" "Item42\n" "Item43\n" "Item44\n" "Item45\n" "Item46\n" "Item47\n" "Item48\n" "Item49\n" "Item50\n" "Item51\n" "Item52\n" "Item53\n" "Item54\n" "Item55\n" "Item56\n" "Item57\n" "Item58\n" "Item59\n" "Item60\n" "Item61\n" "Item62\n" "Item63\n" "Item64\n" "Item65\n" "Item66\n" "Item67\n" "Item68\n" "Item69\n" "Item70\n" "Item71\n" "Item72\n" "Item73\n" "Item74\n" "Item75\n" "Item76\n" "Item77\n" "Item78\n" "Item79\n" "Item80\n" "Item81\n" "Item82\n" "Item83\n" "Item84\n" "Item85\n" "Item86\n" "Item87\n" "Item88\n" "Item89\n" "Item90\n" "Item91\n" "Item92\n" "Item93\n" "Item94\n" "Item95\n" "Item96\n" "Item97\n" "Item98\n" "Item99\n" "Item100 ") 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