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

/
/

Test String

Code Generator

Language

Generated Code

$re = '/<span(?!.*? id="textmarker).*?">/'; $str = '<p style="font-size: inherit; display: block; margin-bottom: 1em; margin-top: 0px;">It’s worth elaborating on the latter point. There are all sorts of things it would be morally good to do, but that would involve such great personal sacrifice that nobody could reasonably<span class="Apple-converted-space">&nbsp;</span>expect<span class="Apple-converted-space">&nbsp;</span>it (of others or of themselves).<span class="Apple-converted-space">&nbsp;</span><span id="textmarker_14">Donating half your income to the most<span class="Apple-converted-space">&nbsp;</span></span><span><span id="textmarker_15">cost-effective charities</span></span><span id="textmarker_16" class="textmarker textmarker_8">, as some in the Effective Altruism movement recommend, would be morally outstanding</span>.</p> <p style="font-size: inherit; display: block; margin-bottom: 1em; margin-top: 0px;">This sort of ‘demandingness constraint’ on plausible moral obligations seems all the stronger when it comes to procreative ethics. It’s one thing to ask us to give up a large portion of our salaries. But it would be still<span class="Apple-converted-space">&nbsp;</span><em>more</em><span class="Apple-converted-space">&nbsp;</span>demanding and intrusive to ask that an otherwise fortunately situated woman effectively give up her entire life and autonomy to become a living, breathing baby factory. Even if it would bring about the most impartial good (which doesn’t seem very likely in any case – there might always be better things she could achieve with her life), such a huge personal sacrifice is simply<em>way too much to ask</em><span class="Apple-converted-space">&nbsp;</span>of anyone. So we can reasonably reject the proposed procreative obligation on that basis.</p>'; preg_match($re, $str, $matches, PREG_OFFSET_CAPTURE, 0); // Print the entire match result var_dump($matches);

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