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
No Match

/
/
g

Test String

Code Generator

Language

Generated Code

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = (r"(?:IT|SM)\d{2} ?[A-Z]\d{3}(?: ?\d{4}){4} ?\d{3}|\n" r"CY\d{2} ?[A-Z]\d{3}(?: ?\d{4}){5}|\n" r"NL\d{2} ?[A-Z]{4}(?: ?\d{4}){2} ?\d{2}|\n" r"LV\d{2} ?[A-Z]{4}(?: ?\d{4}){3} ?\d|\n" r"(?:BG|BH|GB|IE)\d{2} ?[A-Z]{4}(?: ?\d{4}){3} ?\d{2}|\n" r"GI\d{2} ?[A-Z]{4}(?: ?\d{4}){3} ?\d{3}|\n" r"RO\d{2} ?[A-Z]{4}(?: ?\d{4}){4}|\n" r"KW\d{2} ?[A-Z]{4}(?: ?\d{4}){5} ?\d{2}|\n" r"MT\d{2} ?[A-Z]{4}(?: ?\d{4}){5} ?\d{3}|\n" r"NO\d{2}(?: ?\d{4}){4}|\n" r"(?:DK|FI|GL|FO)\d{2}(?: ?\d{4}){3} ?\d{2}|\n" r"MK\d{2}(?: ?\d{4}){3} ?\d{3}|\n" r"(?:AT|EE|KZ|LU|XK)\d{2}(?: ?\d{4}){4}|\n" r"(?:BA|HR|LI|CH|CR)\d{2}(?: ?\d{4}){4} ?\d|\n" r"(?:GE|DE|LT|ME|RS)\d{2}(?: ?\d{4}){4} ?\d{2}|\n" r"IL\d{2}(?: ?\d{4}){4} ?\d{3}|\n" r"(?:AD|CZ|ES|MD|SA)\d{2}(?: ?\d{4}){5}|\n" r"PT\d{2}(?: ?\d{4}){5} ?\d|\n" r"(?:BE|IS)\d{2}(?: ?\d{4}){5} ?\d{2}|\n" r"(?:FR|MR|MC)\d{2}(?: ?\d{4}){5} ?\d{3}|\n" r"(?:AL|DO|LB|PL)\d{2}(?: ?\d{4}){6}|\n" r"(?:AZ|HU)\d{2}(?: ?\d{4}){6} ?\d|\n" r"(?:GR|MU)\d{2}(?: ?\d{4}){6} ?\d{2}") test_str = ("IT12 A123 1234 1234 1234 1234 123\n" "IT12A1231234123412341234123\n" "CY12 A123 1234 1234 1234 1234 1234\n" "CY12A12312341234123412341234\n" "NL12 ABCD 1234 1234 12\n" "NL12ABCD1234123412\n" "LV12 ABCD 1234 1234 1234 1\n" "LV12ABCD1234123412341\n" "BG12 ABCD 1234 1234 1234 12\n" "BG12ABCD12341234123412\n" "GI12 ABCD 1234 1234 1234 123\n" "GI12ABCD123412341234123\n" "RO12 ABCD 1234 1234 1234 1234\n" "RO12ABCD1234123412341234\n" "KW12 ABCD 1234 1234 1234 1234 1234 12\n" "KW12ABCD1234123412341234123412\n" "MT12 ABCD 1234 1234 1234 1234 1234 123\n" "MT12ABCD12341234123412341234123\n" "NO12 1234 1234 1234 1234\n" "NO121234123412341234\n" "DK12 1234 1324 1234 12\n" "DK1212341324123412\n" "MK12 1234 1234 1234 123\n" "MK12123412341234123\n" "AT12 1234 1234 1234 1234\n" "AT121234123412341234\n" "BA12 1234 1234 1234 1234 1\n" "BA1212341234123412341\n" "DE12 1234 1234 1234 1234 12\n" "DE12123412341234123412\n" "IL12 1234 1234 1234 1234 123\n" "IL121234123412341234123\n" "CZ12 1234 1234 1234 1234 1234\n" "CZ1212341234123412341234\n" "PT12 1234 1234 1234 1234 1234 1\n" "PT12123412341234123412341\n" "BE12 1234 1234 1234 1234 1234 12\n" "BE121234123412341234123412\n" "FR12 1234 1234 1234 1234 1234 123\n" "FR1212341234123412341234123\n" "AL12 1234 1234 1234 1234 1234 1234\n" "AL12123412341234123412341234\n" "AZ12 1234 1234 1234 1234 1234 1234 1\n" "AZ121234123412341234123412341\n" "GR12 1234 1234 1234 1234 1234 1234 12\n" "GR1212341234123412341234123412") matches = re.finditer(regex, test_str) for matchNum, match in enumerate(matches, start=1): print ("Match {matchNum} was found at {start}-{end}: {match}".format(matchNum = matchNum, start = match.start(), end = match.end(), match = match.group())) for groupNum in range(0, len(match.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = match.start(groupNum), end = match.end(groupNum), group = match.group(groupNum))) # Note: for Python 2.7 compatibility, use ur"" to prefix the regex and u"" to prefix the test string and substitution.

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