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
Processing...

Test String

Code Generator

Language

Generated Code

const regex = /https?:\/\/\S*"/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('https?:\\\/\\\/\\S*"', 'gm') const str = `{"created_at": "Fri Aug 12 10:04:00 +0000 2016", "id": 764039724818272256, "text": "@theblaze https://t.co/TY9DlZ584c @realDonaldTrump ", "in_reply_to_screen_name": "theblaze", "user": {"id": 366636488, "id_str": "366636488", "name": "GIL DUPUY", "screen_name": "DUPUY77", "location": "Miami", "url": "http://ggm-dupuy.com", "description": "Fashion photographer, love action and adventure, care for the less fortunate, don't tolerate any kind of racism regardless of race or religion", "verified": false, "followers_count": 186, "friends_count": 446, "utc_offset": null, "time_zone": null, "lang": "en", "default_profile_image": false, "following": null, "notifications": null}, "geo": null, "coordinates": null, "place": {"name": "Frontenac", "full_name": "Frontenac, MO", "country_code": "US", "country": "United States", "attributes": {}}, "retweet_count": 0, "favorite_count": 0, "extended_entities": {"media": [{"id": 764039718237409281, "id_str": "764039718237409281", "indices": [27, 50], "media_url": "http://pbs.twimg.com/media/CppqE1_UkAE2qFj.jpg", "media_url_https": "https://pbs.twimg.com/media/CppqE1_UkAE2qFj.jpg", "url": "https://t.co/TY9DlZ584c", "display_url": "pic.twitter.com/TY9DlZ584c", "expanded_url": "http://twitter.com/DUPUY77/status/764039724818272256/photo/1", "type": "photo", "sizes": {"medium": {"w": 640, "h": 1136, "resize": "fit"}, "large": {"w": 640, "h": 1136, "resize": "fit"}, "thumb": {"w": 150, "h": 150, "resize": "crop"}, "small": {"w": 383, "h": 680, "resize": "fit"}}}]}, "favorited": false, "retweeted": false, "possibly_sensitive": false, "lang": "und"}`; // 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