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

/
/
g

Test String

Code Generator

Language

Generated Code

re = /(\\u001b)(8|7|H|>|\[(\?\d+(h|l)|[0-2]?(K|J)|\d*(A|B|C|D\D|E|F|G|g|i|m|n|S|s|T|u)|1000D\d+|\d*;\d*(f|H|r|m)|\d+;\d+;\d+m))/ str = '\\u001b7 \\u001b8 \\u001bH \\u001b> \\u001b[K \\u001b[0K \\u001b[J \\u001b[2J \\u001b[10A \\u001b[10B \\u001b[10C \\u001b[10D \\u001b[10E \\u001b[10F \\u001b[10S \\u001b[10T \\u001b[10G \\u001b[8C \\u001b[s \\u001b[u \\u001b[1000D22 \\u001b[999;999H \\u001b[1;1H \\u001b[1;1f \\u001b[1;24r \\u001b[6n \\u001b[5i \\u001b[4i \\u001b[3g \\u001b[?7h \\u001b[?25h \\u001b[?25l \\u001b[0m \\u001b[31m \\u001b[41m \\u001b[1m \\u001b[4m \\u001b[5m \\u001b[7m \\u001b[8m \\u001b[31;1m \\u001b[41;1m \\u001b[38;5;255m \\u001b[48;5;255m' # Print the match result str.scan(re) do |match| puts match.to_s end

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 Ruby, please visit: http://ruby-doc.org/core-2.2.0/Regexp.html