Regular Expressions 101

Save & Share

Flavor

  • PCRE2 (PHP >=7.3)
  • PCRE (PHP <7.3)
  • ECMAScript (JavaScript)
  • Python
  • Golang
  • Java 8
  • .NET 7.0 (C#)
  • Rust
  • Regex Flavor Guide

Function

  • Match
  • Substitution
  • List
  • Unit Tests

Tools

Sponsors
There are currently no sponsors. Become a sponsor today!
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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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 = '/\[([0-9]{4}\.[0-9]{2}\.[0-9]{2} [0-9]{2}:[0-9]{2}:[0-9]{2})\] \[([a-zA-Z]+)\] \[(.+)\] \[(.+)\] (.*)/m'; $str = '[2019.01.10 22:45:37] [INFO] [main] [Config] Starting to load configuration! [2019.01.10 22:45:38] [WARN] [main] [Config] Value for key: shard_num was not provided! Using default value: "-1" [2019.01.10 22:45:39] [WARN] [main] [Config] Value for key: default_prefix was not provided! Using default value: ";" [2019.01.10 22:45:39] [WARN] [main] [Config] Value for key: haste.server was not provided! Using default value: "https://hastebin.com/documents" [2019.01.10 22:45:39] [WARN] [main] [Config] Value for key: haste.link was not provided! Using default value: "https://hastebin.com/" [2019.01.10 22:45:39] [INFO] [main] [Config] Finished loading configuration! [2019.01.10 22:45:43] [INFO] [main] [ShardManager] Login Successful! [2019.01.10 22:45:43] [INFO] [main] [Command Manager] Loaded 7 commands in 85ms. [2019.01.10 22:45:43] [INFO] [JDA [0 / 1] MainWS-WriteThread] [WebSocketClient] Connected to WebSocket [2019.01.10 22:45:43] [INFO] [JDA [0 / 1] MainWS-ReadThread] [JDA] Finished Loading! [2019.01.10 22:45:43] [INFO] [JDA [0 / 1] MainWS-ReadThread] [CascadeBot] All shards successfully logged in!'; preg_match_all($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