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

/
/
gm

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"\w+-gradient\(.*?\)\)|\w+-gradient\(.*?\)" test_str = ("Only Match CSS gradients ignoring everything else.\n\n" "EXAMPLES\n\n" "2 and 3+ colors any type (4 matches): \\w+-gradient\\(.*?\\)\\)|\\w+-gradient\\(.*?\\)\n" "3+ colors linear (1 match): linear-gradient\\(.*?\\)\\)\n" "2 colors linear (4 matches): linear-gradient\\(.*?\\)\n" "2 colors any type (4 matches): \\w+-gradient\\(.*?\\)\n\n" "---\n\n" "linear-gradient(148deg, #c2fd88 24%, #89fc80 100%); //green\n" "linear-gradient(148deg, #fff 24%, #000 100%); //gray\n" "`background-image: linear-gradient(to right, rgb(236, 72, 153), rgb(239, 68, 68), rgb(234, 179, 8));`\n" "$highlight-rainbow: conic-gradient(from 195.94deg at 50% 50%, #FF1B71 -28.98deg, #E0201A 0.41deg, #EE3F16 27.93deg, #FF6128 54.73deg, #FDA206 88.8deg, #FFED00 117.65deg, #DFF051 145.77deg, #17AB70 175.77deg, #1A8F9C 207.65deg, #005AFF 239.36deg, #5C4ECE 274.87deg, #582C86 304.33deg, #FF1B71 331.02deg, #E0201A 360.41deg);\n") 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