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

Substitution

Processing...

Code Generator

Language

Generated Code

$re = '/\s*(<!--[\s\S]+?-->)/m'; $str = ' <header class="afl"> <div class="openClose"> <div class="line line1"></div> <div class="line line2"></div> <div class="line line3"></div> </div> <div class="ssLogo"> <div class="c1"> <div class="c2">SS</div> </div> </div> <!-- <script data-xd>mcgu/a-/AAuE7mA5Yb1qpx76aqsJ131_TaqMRgH1jd5nVUYrO9yDGQ=s96-c</script> --> <!-- <script data-xd>mcgu/a-/AAuE7mA5Yb1qpx76aqsJ131_TaqMRgH1jd5nVUYrO9yDGQ=s96-c</script><script data-xd>mcgu/a-/AAuE7mA5Yb1qpx76aqsJ131_TaqMRgH1jd5nVUYrO9yDGQ=s96-c</script> <script data-xd>mcgu/a-/AAuE7mA5Yb1qpx76aqsJ131_TaqMRgH1jd5nVUYrO9yDGQ=s96-c</script><script data-xd>mcgu/a-/AAuE7mA5Yb1qpx76aqsJ131_TaqMRgH1jd5nVUYrO9yDGQ=s96-c</script> <script data-xd>mcgu/a-/AAuE7mA5Yb1qpx76aqsJ131_TaqMRgH1jd5nVUYrO9yDGQ=s96-c</script><script data-xd>mcgu/a-/AAuE7mA5Yb1qpx76aqsJ131_TaqMRgH1jd5nVUYrO9yDGQ=s96-c</script> <script data-xd>mcgu/a-/AAuE7mA5Yb1qpx76aqsJ131_TaqMRgH1jd5nVUYrO9yDGQ=s96-c</script><script data-xd>mcgu/a-/AAuE7mA5Yb1qpx76aqsJ131_TaqMRgH1jd5nVUYrO9yDGQ=s96-c</script> <script data-xd>mcgu/a-/AAuE7mA5Yb1qpx76aqsJ131_TaqMRgH1jd5nVUYrO9yDGQ=s96-c</script><script data-xd>mcgu/a-/AAuE7mA5Yb1qpx76aqsJ131_TaqMRgH1jd5nVUYrO9yDGQ=s96-c</script> tdhuitjhuio5hrtjhtryhtujhtohju --> <div class="ssText">Social Services</div> <div class="menu"> <div class="userData"> <div class="logo"> <img class="userpicture" src="https://lh3.googleusercontent.com/a-/AAuE7mA5Yb1qpx76aqsJ131_TaqMRgH1jd5nVUYrO9yDGQ=s96-c" alt="MD Real" /> </div> </div> </div> </header> <aside class="leftSidebar open" id="menu"> <div class="controls"> <div class="openClose"> <div class="line line1"></div> <div class="line line2"></div> <div class="line line3"></div> </div> </div> <!-- <script data-xd>mcgu/a-/AAuE7mA5Yb1qpx76aqsJ131_TaqMRgH1jd5nVUYrO9yDGQ=s96-c</script> --> <!-- <script data-xd>mcgu/a-/AAuE7mA5Yb1qpx76aqsJ131_TaqMRgH1jd5nVUYrO9yDGQ=s96-c</script><script data-xd>mcgu/a-/AAuE7mA5Yb1qpx76aqsJ131_TaqMRgH1jd5nVUYrO9yDGQ=s96-c</script> <script data-xd>mcgu/a-/AAuE7mA5Yb1qpx76aqsJ131_TaqMRgH1jd5nVUYrO9yDGQ=s96-c</script><script data-xd>mcgu/a-/AAuE7mA5Yb1qpx76aqsJ131_TaqMRgH1jd5nVUYrO9yDGQ=s96-c</script> <script data-xd>mcgu/a-/AAuE7mA5Yb1qpx76aqsJ131_TaqMRgH1jd5nVUYrO9yDGQ=s96-c</script><script data-xd>mcgu/a-/AAuE7mA5Yb1qpx76aqsJ131_TaqMRgH1jd5nVUYrO9yDGQ=s96-c</script> <script data-xd>mcgu/a-/AAuE7mA5Yb1qpx76aqsJ131_TaqMRgH1jd5nVUYrO9yDGQ=s96-c</script><script data-xd>mcgu/a-/AAuE7mA5Yb1qpx76aqsJ131_TaqMRgH1jd5nVUYrO9yDGQ=s96-c</script> <script data-xd>mcgu/a-/AAuE7mA5Yb1qpx76aqsJ131_TaqMRgH1jd5nVUYrO9yDGQ=s96-c</script><script data-xd>mcgu/a-/AAuE7mA5Yb1qpx76aqsJ131_TaqMRgH1jd5nVUYrO9yDGQ=s96-c</script> tdhuitjhuio5hrtjhtryhtujhtohju --> <div id="system" class="system" data-textarea="Social Services"> <a href="" data-content="Our Requirements"></a> <a href="" data-content="API\'s List"></a> </div> <div id="user" class="userDatas" data-textarea="User"> <a href="" data-content="About User"></a> <a href="" data-content="User Requests"></a> <a href="" data-content="Enabled API\'s"></a> </div> </aside> <section id="userDetails"></section> <section class="content"></section> <footer></footer> <!-- <script data-xd>mcgu/a-/AAuE7mA5Yb1qpx76aqsJ131_TaqMRgH1jd5nVUYrO9yDGQ=s96-c</script> --> <!-- <script data-xd>mcgu/a-/AAuE7mA5Yb1qpx76aqsJ131_TaqMRgH1jd5nVUYrO9yDGQ=s96-c</script><script data-xd>mcgu/a-/AAuE7mA5Yb1qpx76aqsJ131_TaqMRgH1jd5nVUYrO9yDGQ=s96-c</script> <script data-xd>mcgu/a-/AAuE7mA5Yb1qpx76aqsJ131_TaqMRgH1jd5nVUYrO9yDGQ=s96-c</script><script data-xd>mcgu/a-/AAuE7mA5Yb1qpx76aqsJ131_TaqMRgH1jd5nVUYrO9yDGQ=s96-c</script> <script data-xd>mcgu/a-/AAuE7mA5Yb1qpx76aqsJ131_TaqMRgH1jd5nVUYrO9yDGQ=s96-c</script><script data-xd>mcgu/a-/AAuE7mA5Yb1qpx76aqsJ131_TaqMRgH1jd5nVUYrO9yDGQ=s96-c</script> <script data-xd>mcgu/a-/AAuE7mA5Yb1qpx76aqsJ131_TaqMRgH1jd5nVUYrO9yDGQ=s96-c</script><script data-xd>mcgu/a-/AAuE7mA5Yb1qpx76aqsJ131_TaqMRgH1jd5nVUYrO9yDGQ=s96-c</script> <script data-xd>mcgu/a-/AAuE7mA5Yb1qpx76aqsJ131_TaqMRgH1jd5nVUYrO9yDGQ=s96-c</script><script data-xd>mcgu/a-/AAuE7mA5Yb1qpx76aqsJ131_TaqMRgH1jd5nVUYrO9yDGQ=s96-c</script> tdhuitjhuio5hrtjhtryhtujhtohju -->'; $subst = ""; $result = preg_replace($re, $subst, $str); echo "The result of the substitution is ".$result;

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 PHP, please visit: http://php.net/manual/en/ref.pcre.php