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"^([\"']?)(\$?([0-9]{1,3},([0-9]{3},?)*[0-9]{3}|[0-9]{1,3})((.[0-9]{0,3})[0-9]{0,10})?)\1$", flags=re.MULTILINE) test_str = ("123456\n" "123.\n" ".\n" ".123\n" "123.154574\n" ".545.4584\n" "+1454\n" "+487.54587\n" "-54587.7487\n" ".1225-\n" ".456+\n" "454.4+\n" "454.455874\n" "45.45745687687.5678\n" "45,547\n" "45,5\n" ",154567891021\n" "0,154567891021\n" "123,1023458748\n" "4546587,54587867\n" "578,4\n" "0\n" ".123\n" "0.00145\n" "0.0\n" "012345678910\n" "1,345.154\n" "4,330,234.34\n" "5.545445454\n" "3,023,123.34\n" "12.1\n" "5,356.12345678910\n" "1.20\n" "1.01\n" "0.52\n" "125.30\n" "158,265.36\n" "100,100,100,123,125,568,000.00\n" "\"\"\n" "''\n" "\"1\"\n" "'1'\n" "\"123\"\n" "'123'\n" "\"123.1\"\n" "'0'\n" "\"123.12345647891\"\n" "\"19,741.24\"\n" "1234567891023154546574568768767866876767676876584764646546546465465464564564.240\n" "\"191741.240\"") 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