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

/
/
gm

Test String

Code Generator

Generated Code

$re = '/(?<=[\.,;\s\t\n])[a-z0-9\-]{2,}(?=[\.,;\s\t\n])/m'; $str = ' -a- -a-ll- [Enter KING HENRY, LORD JOHN OF , -,the;, LANCASTER , , the EARL !and =all =12 ,123-,;, -qw !all a-a -doof I -i ,9ab+ xxx xx x !all ?nicht !and -doof -12 -aa of WESTMORELAND, SIR WALTER BLUNT, and others] 12 d12a ; a1 d1a, ! ,aaaaa aaa ,aa1 .1a , ; !.a12 KING HENRY IV So !shaken as we, the are, so wan with care, Find we a time; for frighted peace to pant, And breathe short-winded accents of new broils To be commenced in strands afar remote. No more the thirsty entrance of this soil Shall 12 daub her 1l1ips with her own children\'s blood; Nor more shall trenching war channel her fields, Nor bruise her flowerets with the armed hoofs Of hostile paces: those opposed eyes, Which, like the meteors of a troubled heaven, All of one nature, of one substance bred, Did lately meet in the intestine shock And furious close of civil butchery Shall now, in mutual well-beseeming ranks, March all one way and be no more opposed Against acquaintance, kindred and allies: The edge of war, like an ill-sheathed knife, No more shall cut his master. Therefore, friends, As far as to the sepulchre of Christ, Whose soldier now, under whose blessed cross We are impressed and engaged to fight, Forthwith a power of English shall we levy; Whose arms were moulded in their mothers\' womb To chase these pagans in those holy fields Over whose acres walk\'d those blessed feet Which fourteen hundred years ago were nail\'d For our advantage on the bitter cross. But this our purpose now is twelve month old, And bootless \'tis to tell you we will go: Therefore we meet not now. Then let me hear of you, my gentle cousin Westmoreland, What yesternight our council did decree In forwarding this dear expedience. WESTMORELAND my liege, this haste was hot in question, '; preg_match_all($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