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

const regex = /^\[([\d]{1,2}-[\w]{3,9}-[\d]{4}\s+[\d]{2}:[\d]{2}:[\d]{2}\s+[A-Z]{3,4})\]\s((?s).+?)(?=(?:^\[.+\])|\Z)/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('^\\[([\\d]{1,2}-[\\w]{3,9}-[\\d]{4}\\s+[\\d]{2}:[\\d]{2}:[\\d]{2}\\s+[A-Z]{3,4})\\]\\s((?s).+?)(?=(?:^\\[.+\\])|\\Z)', 'gm') const str = `[27-May-2021 05:59:39 UTC] Inpsyde\\Idealo\\WooCommerce\\IdealoException: Plugin "woocommerce" must be installed and active in C:\\Users\\xedin\\Local Sites\\idealo\\app\\public\\wp-content\\plugins\\idealo-for-woocommerce\\src\\Application.php:172 [27-May-2021 05:59:39 UTC] PHP Fatal error: Uncaught Error: Class 'ActionScheduler_Lock' not found in C:\\Users\\xedin\\Local Sites\\idealo\\app\\public\\wp-content\\plugins\\idealo-for-woocommerce\\vendor\\woocommerce\\action-scheduler\\classes\\abstracts\\ActionScheduler.php:29 Stack trace: #0 C:\\Users\\xedin\\Local Sites\\idealo\\app\\public\\wp-content\\plugins\\idealo-for-woocommerce\\vendor\\woocommerce\\action-scheduler\\classes\\ActionScheduler_QueueRunner.php(103): ActionScheduler::lock() #1 C:\\Users\\xedin\\Local Sites\\idealo\\app\\public\\wp-includes\\class-wp-hook.php(292): ActionScheduler_QueueRunner->maybe_dispatch_async_request('') #2 C:\\Users\\xedin\\Local Sites\\idealo\\app\\public\\wp-includes\\class-wp-hook.php(316): WP_Hook->apply_filters(NULL, Array) #3 C:\\Users\\xedin\\Local Sites\\idealo\\app\\public\\wp-includes\\plugin.php(484): WP_Hook->do_action(Array) #4 C:\\Users\\xedin\\Local Sites\\idealo\\app\\public\\wp-includes\\load.php(1072): do_action('shutdown') #5 [internal function]: shutdown_action_hook() #6 {main} thrown in C:\\Users\\xedin\\Local Sites\\idealo\\app\\public\\wp-content\\plugins\\idealo-for-woocommerce\\vendor\\woocommerce\\action-scheduler\\classes\\abstracts\\ActionScheduler.php on line 29 [27-May-2021 05:59:39 UTC] PHP Stack trace: [27-May-2021 05:59:39 UTC] PHP 1. {main}() C:\\Users\\xedin\\Local Sites\\idealo\\app\\public\\wp-admin\\admin-ajax.php:0 [27-May-2021 05:59:39 UTC] PHP 2. do_action() C:\\Users\\xedin\\Local Sites\\idealo\\app\\public\\wp-admin\\admin-ajax.php:187 [27-May-2021 05:59:39 UTC] PHP 3. WP_Hook->do_action() C:\\Users\\xedin\\Local Sites\\idealo\\app\\public\\wp-includes\\plugin.php:484 [27-May-2021 05:59:39 UTC] PHP 4. WP_Hook->apply_filters() C:\\Users\\xedin\\Local Sites\\idealo\\app\\public\\wp-includes\\class-wp-hook.php:316 [27-May-2021 05:59:39 UTC] PHP 5. wp_ajax_delete_plugin() C:\\Users\\xedin\\Local Sites\\idealo\\app\\public\\wp-includes\\class-wp-hook.php:292 [27-May-2021 05:59:39 UTC] PHP 6. wp_send_json_success() C:\\Users\\xedin\\Local Sites\\idealo\\app\\public\\wp-admin\\includes\\ajax-actions.php:4591 [27-May-2021 05:59:39 UTC] PHP 7. wp_send_json() C:\\Users\\xedin\\Local Sites\\idealo\\app\\public\\wp-includes\\functions.php:4151 [27-May-2021 05:59:39 UTC] PHP 8. wp_die() C:\\Users\\xedin\\Local Sites\\idealo\\app\\public\\wp-includes\\functions.php:4125 [27-May-2021 05:59:39 UTC] PHP 9. _ajax_wp_die_handler() C:\\Users\\xedin\\Local Sites\\idealo\\app\\public\\wp-includes\\functions.php:3421 [27-May-2021 06:56:26 UTC] PHP Warning: mysqli_real_connect(): (HY000/2002): No connection could be made because the target machine actively refused it. in C:\\Users\\xedin\\Local Sites\\idealo\\app\\public\\wp-includes\\wp-db.php on line 1653 [27-May-2021 06:56:27 UTC] PHP Stack trace: [27-May-2021 06:56:27 UTC] PHP 1. {main}() C:\\Users\\xedin\\Local Sites\\idealo\\app\\public\\wp-cron.php:0 [27-May-2021 06:56:27 UTC] PHP 2. require_once() C:\\Users\\xedin\\Local Sites\\idealo\\app\\public\\wp-cron.php:44 [27-May-2021 06:56:27 UTC] PHP 3. require_once() C:\\Users\\xedin\\Local Sites\\idealo\\app\\public\\wp-load.php:37 [27-May-2021 06:56:27 UTC] PHP 4. require_once() C:\\Users\\xedin\\Local Sites\\idealo\\app\\public\\wp-config.php:80 [27-May-2021 06:56:27 UTC] PHP 5. require_wp_db() C:\\Users\\xedin\\Local Sites\\idealo\\app\\public\\wp-settings.php:124 [27-May-2021 06:56:27 UTC] PHP 6. wpdb->__construct() C:\\Users\\xedin\\Local Sites\\idealo\\app\\public\\wp-includes\\load.php:545 [27-May-2021 06:56:27 UTC] PHP 7. wpdb->db_connect() C:\\Users\\xedin\\Local Sites\\idealo\\app\\public\\wp-includes\\wp-db.php:632 [27-May-2021 06:56:27 UTC] PHP 8. mysqli_real_connect() C:\\Users\\xedin\\Local Sites\\idealo\\app\\public\\wp-includes\\wp-db.php:1653 `; // Reset `lastIndex` if this regex is defined globally // regex.lastIndex = 0; let m; while ((m = regex.exec(str)) !== null) { // This is necessary to avoid infinite loops with zero-width matches if (m.index === regex.lastIndex) { regex.lastIndex++; } // The result can be accessed through the `m`-variable. m.forEach((match, groupIndex) => { console.log(`Found match, group ${groupIndex}: ${match}`); }); }

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 JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions