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
  • 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

`
`

Test String

Code Generator

Language

Generated Code

$re = '`(https://[a-zA-Z\d-\.]{0,30}.aaa.com)/t.png\?t=[^&]+&(amp;)*c=m_m`'; $str = 'https://developers.aaa.com/fb/t.png?dmmy=1&fb_sig_in_iframe=1&fb_sig_iframe_key=8e296a067a37563370ded05f5a3bf3ec&fb_sig_locale=bg_BG&fb_sig_in_new_facebook=1&fb_sig_time=1282749119.128&fb_sig_added=1&fb_sig_profile_update_time=1229862039&fb_sig_expires=1282755600&fb_sig_user=761405628&fb_sig_session_key=2.IuyNqrcLQaqPhjzhFiCARg__.3600.1282755600-761405628&fb_sig_ss=igFqJKrhJZWGSRO__Vpx4A__&fb_sig_cookie_sig=a9f110b4fc6a99db01d7d1eb9961fca6&fb_sig_ext_perms=user_birthday,user_religion_politics,user_relationships,user_relationship_details,user_hometown,user_location,user_likes,user_activities,user_interests,user_education_history,user_work_history,user_online_presence,user_website,user_groups,user_events,user_photos,user_videos,user_photo_video_tags,user_notes,user_about_me,user_status,friends_birthday,friends_religion_politics,friends_relationships,friends_relationship_details,friends_hometown,friends_location,friends_likes,friends_activities,friends_interests,friends_education_history,friends_work_history,friends_online_presence,friends_website,friends_groups,friends_events,friends_photos,friends_videos,friends_photo_video_tags,friends_notes,friends_about_me,friends_status&fb_sig_country=bg&fb_sig_api_key=9f7ea9498aabcd12728f8e13369a0528&fb_sig_app_id=177509235268&fb_sig=1a5c6100fa19c1c9b983e2d6ccfc05ef https://a.aaa.com/t.png?t=abcddds&amp;amp;c=m_m https://a.aaa.com/t.png?t=abcddds&amp;amp;c=m_m '; preg_match($re, $str, $matches, PREG_OFFSET_CAPTURE, 0); // Print the entire match result var_dump($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