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 = '/^\[((?!(?:ti|ar|al|au|lr|length|by|offset|re|tool|ve|#|\d{1,2}):.+\]).*)\](\r?\n)(\[\d{1,2}:\d{1,2}\.\d{2,3}\])(.*)$/m'; $str = '[ti:Hey You] [ar:Pink Floyd] [al:The Wall (2011 Remaster)] [au:Roger Waters] [lr:Roger Waters] [length:04:40] [by: Casual Tea] [offset:+300] [re: Musicbee] [tool: Mp3tag] [ve: 1.2.3] [#: A comment] [Acoustic Guitar Intro] [Verse 1: David Gilmour] [00:35.485]Hey you [00:38.184]Out there in the cold, [00:39.828]Getting lonely, getting old, [00:41.848]Can you feel me? [00:46.137]Hey you [00:48.659]Standing in the aisles [00:50.250]With itchy feet and fading smiles, [00:52.611]Can you feel me? [00:57.924]Hey, you, don\'t help them to bury the light [01:08.393]Don\'t give in without a fight [01:13.227] [Verse 2: David Gilmour] [01:20.282]Hey, you [01:23.035]Out there on your own, [01:24.566]Sitting naked by the phone, [01:26.685]Would you touch me? [01:30.958]Hey, you [01:33.071]With your ear against the wall, [01:35.171]Waiting for someone to call out, [01:37.348]Would you touch me? [01:42.711]Hey you, would you help me to carry the stone? [01:52.884]Open your heart, I\'m coming home [01:58.076] [Guitar Solo] [Bridge: Roger Waters] [02:57.282]But it was only fantasy [03:04.137]The wall was too high, as you can see [03:11.617]No matter how he tried, he could not break free [03:19.019]And the worms ate into his brain [03:22.914] [Verse 3: Roger Waters] [03:54.974]Hey, you [03:57.745]Out there on the road, [03:59.261]Always doing what you\'re told, [04:01.459]Can you help me? [04:05.745]Hey, you [04:08.135]Out there beyond the wall, [04:09.899]Breaking bottles in the hall, [04:12.108]Can you help me? [04:17.481]Hey, you, don\'t tell me there\'s no hope at all [04:27.360]Together we stand, divided we fall [Outro: Roger Waters] [04:32.742](We fall) [04:34.133](We fall) [04:35.313](We fall) [04:36.593](We fall) [04:37.885](We fall) [04:39.178](We fall) [04:40.433]'; $subst = "$3($1)$2$3$4"; $result = preg_replace($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