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{3})(?!6{3})[0-8]\d{2}-(?!0{2})\d{2}-(?!0{4})\d{4}$", flags=re.MULTILINE) test_str = ("762-37-6334\n" "429-08-8462\n" "519-75-9429\n" "117-08-6495\n" "544-12-9823\n" "841-01-5655\n" "494-82-9724\n" "568-11-2312\n" "420-42-8078\n" "396-09-7229\n" "869-57-0924\n" "609-44-0934\n" "578-20-1520\n" "835-87-3325\n" "636-03-4578\n" "482-19-1418\n" "364-60-1676\n" "780-23-8549\n" "265-33-9416\n" "221-88-6838\n" "550-13-2720\n" "336-93-2610\n" "193-47-3307\n" "480-82-8373\n" "750-66-0817\n" "122-68-3192\n" "673-84-7164\n" "191-03-8274\n" "412-41-9768\n" "888-21-9775\n" "805-53-9154\n" "150-26-0934\n" "880-42-1378\n" "853-41-1922\n" "467-22-3453\n" "220-91-4157\n" "657-24-3167\n" "229-17-5111\n" "411-38-6337\n" "453-61-4836\n" "123-27-0915\n" "105-56-0050\n" "646-82-7847\n" "105-17-8892\n" "301-70-3833\n") 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