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

Code Generator

Language

Generated Code

$re = '/Rep\d*[a|b|c|d|e]\d\d/m'; $str = 'Rep419a01 Καὶ ὁ Ἀδείμαντος ὑπολαβών, Τί οὖν, ἔφη, ὦ Σώκρατες, Rep419a02 ἀπολογήσῃ, ἐάν τίς σε φῇ μὴ πάνυ τι εὐδαίμονας ποιεῖν Rep419a03 τούτους τοὺς ἄνδρας, καὶ ταῦτα δι᾽ ἑαυτούς, ὧν ἔστι μὲν Rep419a04 ἡ πόλις τῇ ἀληθείᾳ, οἱ δὲ μηδὲν ἀπολαύουσιν ἀγαθὸν τῆς Rep419a05 πόλεως, οἷον ἄλλοι ἀγρούς τε κεκτημένοι καὶ οἰκίας οἰκοδομού– Rep419a06 μενοι καλὰς καὶ μεγάλας, καὶ ταύταις πρέπουσαν κατασκευὴν Rep419a07 κτώμενοι, καὶ θυσίας θεοῖς ἰδίας θύοντες, καὶ ξενοδοκοῦντες, Rep419a08 καὶ δὴ καὶ ἃ νυνδὴ σὺ ἔλεγες, χρυσόν τε καὶ ἄργυρον κεκτη– Rep419a09 μένοι καὶ πάντα ὅσα νομίζεται τοῖς μέλλουσιν μακαρίοις Rep419a10 εἶναι; ἀλλ᾽ ἀτεχνῶς, φαίη ἄν, ὥσπερ ἐπίκουροι μισθωτοὶ ἐν Rep420a01 τῇ πόλει φαίνονται καθῆσθαι οὐδὲν ἄλλο ἢ φρουροῦντες. '; preg_match_all($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