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]
  • Character class intersection
    [\w&&[^\d]]
  • 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
Processing...

Test String

Code Generator

Language

Generated Code

$re = '/(([A-Z_a-z]|\d(?!\d*\. ))(\S*))((?:(?:etc\.|i\.e\.|e\.g\.|\.\.|\w+\.(?![\s")])|[*-]+|\n(?![ \t]*\n| *(?:[*-]|\d+\.))|[\w \'",()\[\];:%&\-/]*?))+(?:([.?!])(?=[\s")]|$)|\n\n|\n(?= *[*-])|\n(?= *\d+\.)|$))/i'; $str = '_variable_ name. _variable_by_itself_ variable_ending_with_a_letter What about... this sentence? "get_id.lua" and "param.lua" are at the same path. why module "common/get_id" not found while "common/Param" could be found. Here\'s a list of things: * one, continued - two. * three, - four - five 1. Numbered one, continued 2. numbered two. 3. numbered three. every sentence starts with a capital. let\'s have that rule. but what is a sentence? 42 is the answer. I got a memory leak of the whole client-chat direcrive. sdf this is a sentence that continues down here. while this is a different sentence. (can we find sentences in brackets?) Sentences sometimes (but not always), contain bracketed sections, e.g. as in this sentence; ok? a sentence with no final punctuation should end if double-spaced authorize.net Node.js filename-ish words & such don\'t terminate a sentence I want to move my website from example.net to example.com blah blah blah. I want to move my website from example.net to example.com blah blah blah I want to move my website from example.net to _xCodexBlockxPlacexHolderx_ example.com blah blah blah. _xCodexBlockxPlacexHolderx_ More than a 10% with 1.5 to 2 global load, etc.) to 1st level Flume collectors. I am using AngularJS 1.3.0, but even after upgrade to 1.4.9 it still happens. (That should be just ONE sentence.) A simple sentence, ending with punctuation. A sentence without end punctuatione, ending with double-space "A sentence in quotes." "Ok with that?" "punctuation after the close quote"! ###This is a heading Text in a link [is part of the sentence][1]. Another sentence. And another sentence? End of file!'; preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0); // Print the entire match result var_dump($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