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

/
/
mg

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"dark:\w+?[^\" ]+" test_str = ("<div class=\"bg-white dark:bg-slate-800 rounded-lg px-6 py-8 ring-1 ring-slate-900/5 shadow-xl\">\n" " <div>\n" " <span class=\"inline-flex items-center justify-center p-2 bg-indigo-500 rounded-md shadow-lg\">\n" " <svg class=\"h-6 w-6 text-white\" xmlns=\"http://www.w3.org/2000/svg\" fill=\"none\" viewBox=\"0 0 24 24\" stroke=\"currentColor\" aria-hidden=\"true\"><!-- ... --></svg>\n" " </span>\n" " </div>\n" " <h3 class=\"text-slate-900 dark:text-white mt-5 text-base font-medium tracking-tight\">Writes Upside-Down</h3>\n" " <p class=\"text-slate-500 dark:text-slate-400 mt-2 text-sm\">\n" " <p class=\"text-slate-500 dark:text-slate-400\">\n" " The Zero Gravity Pen can be used to write in any orientation, including upside-down. It even works in outer space.\n" " </p>\n" "</div>") matches = re.finditer(regex, test_str, re.MULTILINE) 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