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"(<svg .*?)(width=\".*?\").*?(?:height=\".*?\")(.*?>)", flags=re.MULTILINE) test_str = ("<svg xmlns=\"http://www.w3.org/2000/svg\" width=\"20\" height=\"24\" xml:space=\"preserve\">\n" " <path d=\"M13 5h-1V4h1M8 5H7V4h1m5.5-1.8L14.8.9c.2-.2.2-.5 0-.7-.2-.2-.5-.2-.7 0l-1.5 1.5c-.7-.5-1.7-.7-2.6-.7-1 0-1.9.2-2.7.6L5.8.1c-.1-.1-.5-.1-.6 0-.2.2-.2.5 0 .7l1.3 1.3C5 3.3 4 5 4 7h12c0-2-1-3.7-2.5-4.8m5 5.8c-.8 0-1.5.7-1.5 1.5v7c0 .8.7 1.5 1.5 1.5s1.5-.7 1.5-1.5v-7c0-.8-.7-1.5-1.5-1.5m-17 0C.7 8 0 8.7 0 9.5v7c0 .8.7 1.5 1.5 1.5S3 17.3 3 16.5v-7C3 8.7 2.3 8 1.5 8M4 18c0 .6.4 1 1 1h1v3.5c0 .8.7 1.5 1.5 1.5S9 23.3 9 22.5V19h2v3.5c0 .8.7 1.5 1.5 1.5s1.5-.7 1.5-1.5V19h1c.6 0 1-.4 1-1V8H4v10z\"/>\n" "</svg>\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