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"^((AT)(U\d{8})|(BE)(0\d{9})|(BG)(\d{9,10})|(CY)(\d{8}[LX])|(CZ)(\d{8,10})|(DE)(\d{9})|(DK)(\d{8})|(EE)(\d{9})|(EL|GR)(\d{9})|(ES)([\dA-Z]\d{7}[\dA-Z])|(FI)(\d{8})|(FR)([\dA-Z]{2}\d{9})|(HU)(\d{8})|(IE)(\d{7}[A-Z]{2})|(IT)(\d{11})|(LT)(\d{9}|\d{12})|(LU)(\d{8})|(LV)(\d{11})|(MT)(\d{8})|(NL)(\d{9}(B\d{2}|BO2))|(PL)(\d{10})|(PT)(\d{9})|(RO)(\d{2,10})|(SE)(\d{12})|(SI)(\d{8})|(SK)(\d{10}))$", flags=re.IGNORECASE | re.MULTILINE) test_str = ("ATU12345678\n" "BE0123456789\n" "BG123456789\n" "BG1234567890\n" "CY12345678X\n" "CY12345678L\n" "CZ12345678\n" "CZ123456789\n" "CZ1234567890\n" "DE123456789\n" "DK12345678\n" "EE123456789\n" "EL123456789\n" "GR123456789\n" "ESX12345678\n" "ES12345678X\n" "ESX1234567X\n" "FI12345678\n" "FR12345678901\n" "FRX1234567890\n" "FR1X123456789\n" "FRXX123456789\n" "HU12345678\n" "IE1234567WA\n" "IE1234567FA\n" "IT12345678901\n" "LT123456789\n" "LT123456789012\n" "LU12345678\n" "LV12345678901\n" "MT12345678\n" "NL123456789B01\n" "NL123456789BO2\n" "PL1234567890\n" "PT123456789\n" "RO1234567890\n" "SE123456789012\n" "SK1234567890") 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