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

Generated Code

import re regex = re.compile(r"^(?:\d{8}(?:\d{2}(?:\d{2})?)?|\(\+?\d{2,3}\)\s?(?:\d{4}[\s*.-]?\d{4}|\d{3}[\s*.-]?\d{3}|\d{2}([\s*.-]?)\d{2}\1\d{2}(?:\1\d{2})?))$", flags=re.MULTILINE) test_str = ("It can contain open and close parenthesis ex. (55)\n" "It can contin or not '+' char ex. (+52)\n" "It can contain 2 or 3 numbers inside parenthesis ex. (+555) o (+55)\n" "It can contain whitespace between close parenthesis and the next numbers ex. (55) 44332211\n" "The consecutive numbers to the parenthesis must be 6 or 8 numbers ex. (55)443322 o (55)44332211\n" "The consecutive numbers to the parenthesis can contain whitespaces, dashes, asterisks, or colons. ex.(55)44-33-22-11 o (55)44 33 22 11 o (55)44*33*22*11 o (55)44.33.22.11\n" "The consecutive numbers to the parenthesis can be divided in groups of 2, 3 or 4 numbers ex. (55)5544-3322 o (55)55 44 33 22 o (555)444*333\n" "The number format can come in a row of 8, 10 o 12 numbers ex. 55443322 o 5544332211 o 554433221100\n" "(55)test\n" "(55)333-test\n" "(55)test 22\n" "554433221100\n" "5544332211\n" "55443322\n" "(55)443322\n" "(55)44332211\n" "(+55)443322\n" "(+55)44332211\n" "(55)4433*2211\n" "(55)444.333\n" "(55)44-33-22-11\n" "(55)4433-2211\n" "(+55)443 322") 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