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]
  • Character class intersection
    [\w&&[^\d]]
  • 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"^(ATU[0-9]{8}|BE0[0-9]{9}|BG[0-9]{9,10}|CY[0-9]{8}L|CZ[0-9]{8,10}|DE[0-9]{9}|DK[0-9]{8}|EE[0-9]{9}|(EL|GR)[0-9]{9}|ES[0-9A-Z][0-9]{7}[0-9A-Z]|FI[0-9]{8}|FR[0-9A-Z]{2}[0-9]{9}|GB([0-9]{9}([0-9]{3})?|[A-Z]{2}[0-9]{3})|HU[0-9]{8}|IE[0-9]S[0-9]{5}L|IT[0-9]{11}|LT([0-9]{9}|[0-9]{12})|LU[0-9]{8}|LV[0-9]{11}|MT[0-9]{8}|NL[0-9]{9}B[0-9]{2}|PL[0-9]{10}|PT[0-9]{9}|RO[0-9]{2,10}|SE[0-9]{12}|SI[0-9]{8}|SK[0-9]{10})$") test_str = "" 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