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

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "<div class=\"category-gallery-item\">\\n(?:.*)<a href=\"\\/wiki\\/[^\"]*\" title=\"[^\"]*\">\\n(?:.*)<div class=\"category-gallery-item-image\">\\n(?:.*)https:\\/\\/images\\.wikia\\.nocookie\\.net\\/(?:.*)\\/americanhorrorstory\\/images\\/thumb\\/(?P<filepath>[^\\/]\\/[^\\/]{2}\\/[^\\/]*)\\/(?:.*)\\n(?:.*)\\n(?:.*)<div class=\"title\">(?P<title>[^\\n]*)<\\/div>\\n\\s*<\\/a>\\n\\s*<\\/div>"; final String string = "<div class=\"category-gallery-room1\">\n" + " <div class=\"category-gallery-item\">\n" + " <a href=\"/wiki/Tate_Langdon\" title=\"Tate Langdon\">\n" + " <div class=\"category-gallery-item-image\">\n" + " <img src=\"https://images.wikia.nocookie.net/__cb20170918121337/americanhorrorstory/images/thumb/6/6a/MurderHouse3.jpg/130px-0%2C1879%2C30%2C1692-MurderHouse3.jpg\" alt=\"Tate Langdon\" width=\"130\" height=\"115\">\n" + " </div>\n" + " <div class=\"title\">Tate Langdon</div>\n" + " </a>\n" + "</div>\n\n" + "<div class=\"category-gallery-item\">\n" + " <a href=\"/wiki/Constance_Langdon\" title=\"Constance Langdon\">\n" + " <div class=\"category-gallery-item-image\">\n" + " <img src=\"https://images.wikia.nocookie.net/__cb20170901150853/americanhorrorstory/images/thumb/0/01/Scnet_ahs_promos01_019.jpg/130px-0%2C1881%2C32%2C1696-Scnet_ahs_promos01_019.jpg\" alt=\"Constance Langdon\" width=\"130\" height=\"115\">\n" + " </div>\n" + " <div class=\"title\">Constance Langdon</div>\n" + " </a>\n" + "</div>\n\n" + "<div class=\"category-gallery-item\">\n" + " <a href=\"/wiki/Infantata\" title=\"Infantata\">\n" + " <div class=\"category-gallery-item-image\">\n" + " <img src=\"https://images.wikia.nocookie.net/__cb20140211011227/americanhorrorstory/images/thumb/8/8a/Infantata-benjamin-woolf-american-horror-story-3.png/130px-139%2C616%2C0%2C421-Infantata-benjamin-woolf-american-horror-story-3.png\" alt=\"Infantata\" width=\"130\" height=\"115\">\n" + " </div>\n" + " <div class=\"title\">Infantata</div>\n" + " </a>\n" + "</div>\n\n" + "<div class=\"category-gallery-item\">\n" + " <a href=\"/wiki/Moira_O%27Hara\" title=\"Moira O'Hara\">\n" + " <div class=\"category-gallery-item-image\">\n" + " <img src=\"https://images.wikia.nocookie.net/__cb20161118211513/americanhorrorstory/images/thumb/1/11/Moira_double.jpg/130px-0%2C250%2C5%2C226-Moira_double.jpg\" alt=\"Moira O'Hara\" width=\"130\" height=\"115\">\n" + " </div>\n" + " <div class=\"title\">Moira O'Hara</div>\n" + " </a>\n" + "</div>\n\n" + "<div class=\"category-gallery-item\">\n" + " <a href=\"/wiki/Vivien_Harmon\" title=\"Vivien Harmon\">\n" + " <div class=\"category-gallery-item-image\">\n" + " <img src=\"https://images.wikia.nocookie.net/__cb20170901162145/americanhorrorstory/images/thumb/9/92/02e87f12aa77ee5561190934d0563538.jpg/130px-0%2C2033%2C35%2C1833-02e87f12aa77ee5561190934d0563538.jpg\" alt=\"Vivien Harmon\" width=\"130\" height=\"115\">\n" + " </div>\n" + " <div class=\"title\">Vivien Harmon</div>\n" + " </a>\n" + "</div>\n\n" + "<div class=\"category-gallery-item\">\n" + " <a href=\"/wiki/Billie_Dean_Howard\" title=\"Billie Dean Howard\">\n" + " <div class=\"category-gallery-item-image\">\n" + " <img src=\"https://images.wikia.nocookie.net/__cb20161016014729/americanhorrorstory/images/thumb/d/d8/Billie_Dean_Howard_-_Hotel.jpg/130px-75%2C528%2C0%2C400-Billie_Dean_Howard_-_Hotel.jpg\" alt=\"Billie Dean Howard\" width=\"130\" height=\"115\">\n" + " </div>\n" + " <div class=\"title\">Billie Dean Howard</div>\n" + " </a>\n" + "</div>\n\n" + "<div class=\"category-gallery-item\">\n" + " <a href=\"/wiki/Violet_Harmon\" title=\"Violet Harmon\">\n" + " <div class=\"category-gallery-item-image\">\n" + " <img src=\"https://images.wikia.nocookie.net/__cb20170831083449/americanhorrorstory/images/thumb/d/d4/Taissa-farmiga-as-violet-harmon-in-american-horror-story-1.jpg/130px-0%2C390%2C6%2C351-Taissa-farmiga-as-violet-harmon-in-american-horror-story-1.jpg\" alt=\"Violet Harmon\" width=\"130\" height=\"115\">\n" + " </div>\n" + " <div class=\"title\">Violet Harmon</div>\n" + " </a>\n" + "</div>\n\n" + "<div class=\"category-gallery-item\">\n" + " <a href=\"/wiki/Hayden_McClaine\" title=\"Hayden McClaine\">\n" + " <div class=\"category-gallery-item-image\">\n" + " <img src=\"https://images.wikia.nocookie.net/__cb20121211204512/americanhorrorstory/images/thumb/9/97/Download_%288%29.jpg/130px-156%2C700%2C0%2C480-Download_%288%29.jpg\" alt=\"Hayden McClaine\" width=\"130\" height=\"115\">\n" + " </div>\n" + " <div class=\"title\">Hayden McClaine</div>\n" + " </a>\n" + "</div>\n\n" + "<div class=\"category-gallery-item\">\n" + " <a href=\"/wiki/Ben_Harmon\" title=\"Ben Harmon\">\n" + " <div class=\"category-gallery-item-image\">\n" + " <img src=\"https://images.wikia.nocookie.net/__cb20170901161948/americanhorrorstory/images/thumb/4/45/Scnet_ahs_promos01_001.jpg/130px-0%2C1573%2C28%2C1420-Scnet_ahs_promos01_001.jpg\" alt=\"Ben Harmon\" width=\"130\" height=\"115\">\n" + " </div>\n" + " <div class=\"title\">Ben Harmon</div>\n" + " </a>\n" + "</div>\n\n" + "<div class=\"category-gallery-item\">\n" + " <a href=\"/wiki/Beauregard_Langdon\" title=\"Beauregard Langdon\">\n" + " <div class=\"category-gallery-item-image\">\n" + " <img src=\"https://images.wikia.nocookie.net/__cb20121029040849/americanhorrorstory/images/thumb/7/78/Beau2.png/130px-161%2C916%2C0%2C667-Beau2.png\" alt=\"Beauregard Langdon\" width=\"130\" height=\"115\">\n" + " </div>\n" + " <div class=\"title\">Beauregard Langdon</div>\n" + " </a>\n" + "</div>\n\n" + "<div class=\"category-gallery-item\">\n" + " <a href=\"/wiki/Adelaide_Langdon\" title=\"Adelaide Langdon\">\n" + " <div class=\"category-gallery-item-image\">\n" + " <img src=\"https://images.wikia.nocookie.net/__cb20170901143540/americanhorrorstory/images/thumb/1/10/Scnet_ahs_promos01_025.jpg/130px-0%2C1805%2C29%2C1626-Scnet_ahs_promos01_025.jpg\" alt=\"Adelaide Langdon\" width=\"130\" height=\"115\">\n" + " </div>\n" + " <div class=\"title\">Adelaide Langdon</div>\n" + " </a>\n" + "</div>\n\n" + "<div class=\"category-gallery-item\">\n" + " <a href=\"/wiki/Larry_Harvey\" title=\"Larry Harvey\">\n" + " <div class=\"category-gallery-item-image\">\n" + " <img src=\"https://images.wikia.nocookie.net/__cb20170831083606/americanhorrorstory/images/thumb/d/d0/American-horror-story-denis-ohare-4.jpg/130px-0%2C540%2C9%2C487-American-horror-story-denis-ohare-4.jpg\" alt=\"Larry Harvey\" width=\"130\" height=\"115\">\n" + " </div>\n" + " <div class=\"title\">Larry Harvey</div>\n" + " </a>\n" + "</div>\n\n" + "<div class=\"category-gallery-item\">\n" + " <a href=\"/wiki/Nora_Montgomery\" title=\"Nora Montgomery\">\n" + " <div class=\"category-gallery-item-image\">\n" + " <img src=\"https://images.wikia.nocookie.net/__cb20140212014448/americanhorrorstory/images/thumb/9/9f/Tumblr_mm7qwzHIgM1rjrfw0o1_500.png/130px-94%2C410%2C0%2C279-Tumblr_mm7qwzHIgM1rjrfw0o1_500.png\" alt=\"Nora Montgomery\" width=\"130\" height=\"115\">\n" + " </div>\n" + " <div class=\"title\">Nora Montgomery</div>\n" + " </a>\n" + "</div>\n\n" + "<div class=\"category-gallery-item\">\n" + " <a href=\"/wiki/Charles_Montgomery\" title=\"Charles Montgomery\">\n" + " <div class=\"category-gallery-item-image\">\n" + " <img src=\"https://images.wikia.nocookie.net/__cb20171012044313/americanhorrorstory/images/thumb/1/1a/Montgomery.jpg/130px-0%2C503%2C9%2C454-Montgomery.jpg\" alt=\"Charles Montgomery\" width=\"130\" height=\"115\">\n" + " </div>\n" + " <div class=\"title\">Charles Montgomery</div>\n" + " </a>\n" + "</div>\n\n" + "<div class=\"category-gallery-item\">\n" + " <a href=\"/wiki/Hugo_Langdon\" title=\"Hugo Langdon\">\n" + " <div class=\"category-gallery-item-image\">\n" + " <img src=\"https://images.wikia.nocookie.net/__cb20121028001711/americanhorrorstory/images/thumb/0/02/Hugo.png/130px-0%2C663%2C10%2C597-Hugo.png\" alt=\"Hugo Langdon\" width=\"130\" height=\"115\">\n" + " </div>\n" + " <div class=\"title\">Hugo Langdon</div>\n" + " </a>\n" + "</div>\n\n" + "<div class=\"category-gallery-item\">\n" + " <a href=\"/wiki/Travis_Wanderly\" title=\"Travis Wanderly\">\n" + " <div class=\"category-gallery-item-image\">\n" + " <img src=\"https://images.wikia.nocookie.net/__cb20111222045635/americanhorrorstory/images/thumb/e/ee/AmericanHorrorStory-travis.jpg/130px-0%2C287%2C4%2C258-AmericanHorrorStory-travis.jpg\" alt=\"Travis Wanderly\" width=\"130\" height=\"115\">\n" + " </div>\n" + " <div class=\"title\">Travis Wanderly</div>\n" + " </a>\n" + "</div>\n" + " </div>\n" + "<div class=\"category-gallery-room1\" style=\"margin-left: 0px;\"><div class=\"category-gallery-item\">\n" + " <a href=\"/wiki/Rubber_Man\" title=\"Rubber Man\">\n" + " <div class=\"category-gallery-item-image\">\n" + " <img src=\"https://images.wikia.nocookie.net/__cb20111216004411/americanhorrorstory/images/thumb/6/61/Ahs1120005_595.jpg/130px-0%2C396%2C8%2C358-Ahs1120005_595.jpg\" alt=\"Rubber Man\" width=\"130\" height=\"115\">\n" + " </div>\n" + " <div class=\"title\">Rubber Man</div>\n" + " </a>\n" + "</div>\n\n" + "<div class=\"category-gallery-item\">\n" + " <a href=\"/wiki/Elizabeth_Short\" title=\"Elizabeth Short\">\n" + " <div class=\"category-gallery-item-image\">\n" + " <img src=\"https://images.wikia.nocookie.net/__cb20121024055325/americanhorrorstory/images/thumb/d/d6/Dahlia2.png/130px-0%2C569%2C10%2C513-Dahlia2.png\" alt=\"Elizabeth Short\" width=\"130\" height=\"115\">\n" + " </div>\n" + " <div class=\"title\">Elizabeth Short</div>\n" + " </a>\n" + "</div>\n\n" + "<div class=\"category-gallery-item\">\n" + " <a href=\"/wiki/Chad_Warwick\" title=\"Chad Warwick\">\n" + " <div class=\"category-gallery-item-image\">\n" + " <img src=\"https://images.wikia.nocookie.net/__cb20111105101300/americanhorrorstory/images/thumb/c/cf/Chad.jpg/130px-0%2C719%2C9%2C645-Chad.jpg\" alt=\"Chad Warwick\" width=\"130\" height=\"115\">\n" + " </div>\n" + " <div class=\"title\">Chad Warwick</div>\n" + " </a>\n" + "</div>\n\n" + "<div class=\"category-gallery-item\">\n" + " <a href=\"/wiki/Marcy\" title=\"Marcy\">\n" + " <div class=\"category-gallery-item-image\">\n" + " <img src=\"https://images.wikia.nocookie.net/__cb20151004153134/americanhorrorstory/images/thumb/8/83/Marcy.jpg/130px-180%2C832%2C0%2C576-Marcy.jpg\" alt=\"Marcy\" width=\"130\" height=\"115\">\n" + " </div>\n" + " <div class=\"title\">Marcy</div>\n" + " </a>\n" + "</div>\n\n" + "<div class=\"category-gallery-item\">\n" + " <a href=\"/wiki/Troy_and_Bryan\" title=\"Troy and Bryan\">\n" + " <div class=\"category-gallery-item-image\">\n" + " <img src=\"https://images.wikia.nocookie.net/__cb20121104143121/americanhorrorstory/images/thumb/6/61/Images_%2835%29.jpg/130px-234%2C1049%2C0%2C720-Images_%2835%29.jpg\" alt=\"Troy and Bryan\" width=\"130\" height=\"115\">\n" + " </div>\n" + " <div class=\"title\">Troy and Bryan</div>\n" + " </a>\n" + "</div>\n\n" + "<div class=\"category-gallery-item\">\n" + " <a href=\"/wiki/Hallie\" title=\"Hallie\">\n" + " <div class=\"category-gallery-item-image\">\n" + " <img src=\"https://images.wikia.nocookie.net/__cb20121115111401/americanhorrorstory/images/thumb/b/b5/Hallie.jpg/130px-0%2C378%2C7%2C341-Hallie.jpg\" alt=\"Hallie\" width=\"130\" height=\"115\">\n" + " </div>\n" + " <div class=\"title\">Hallie</div>\n" + " </a>\n" + "</div>\n\n" + "<div class=\"category-gallery-item\">\n" + " <a href=\"/wiki/Patrick\" title=\"Patrick\">\n" + " <div class=\"category-gallery-item-image\">\n" + " <img src=\"https://images.wikia.nocookie.net/__cb20111105101725/americanhorrorstory/images/thumb/4/40/Pat_2.jpg/130px-0%2C523%2C9%2C472-Pat_2.jpg\" alt=\"Patrick\" width=\"130\" height=\"115\">\n" + " </div>\n" + " <div class=\"title\">Patrick</div>\n" + " </a>\n" + "</div>\n\n" + "<div class=\"category-gallery-item\">\n" + " <a href=\"/wiki/Leah\" title=\"Leah\">\n" + " <div class=\"category-gallery-item-image\">\n" + " <img src=\"https://images.wikia.nocookie.net/__cb20111023041839/americanhorrorstory/images/thumb/c/cd/Leah.jpg/130px-148%2C663%2C0%2C455-Leah.jpg\" alt=\"Leah\" width=\"130\" height=\"115\">\n" + " </div>\n" + " <div class=\"title\">Leah</div>\n" + " </a>\n" + "</div>\n\n" + "<div class=\"category-gallery-item\">\n" + " <a href=\"/wiki/Lorraine_Harvey\" title=\"Lorraine Harvey\">\n" + " <div class=\"category-gallery-item-image\">\n" + " <img src=\"https://images.wikia.nocookie.net/__cb20111117175740/americanhorrorstory/images/thumb/0/0d/Lorraineharveybio.jpg/130px-27%2C411%2C0%2C339-Lorraineharveybio.jpg\" alt=\"Lorraine Harvey\" width=\"130\" height=\"115\">\n" + " </div>\n" + " <div class=\"title\">Lorraine Harvey</div>\n" + " </a>\n" + "</div>\n\n" + "<div class=\"category-gallery-item\">\n" + " <a href=\"/wiki/Luke_(Murder_House)\" title=\"Luke (Murder House)\">\n" + " <div class=\"category-gallery-item-image\">\n" + " <img src=\"https://images.wikia.nocookie.net/__cb20121027065901/americanhorrorstory/images/thumb/4/4f/Luke.png/130px-0%2C524%2C9%2C473-Luke.png\" alt=\"Luke (Murder House)\" width=\"130\" height=\"115\">\n" + " </div>\n" + " <div class=\"title\">Luke (Murder House)</div>\n" + " </a>\n" + "</div>\n\n" + "<div class=\"category-gallery-item\">\n" + " <a href=\"/wiki/R._Franklin\" title=\"R. Franklin\">\n" + " <div class=\"category-gallery-item-image\">\n" + " <img src=\"https://images.wikia.nocookie.net/__cb20121027184749/americanhorrorstory/images/thumb/3/37/Franklin.png/130px-0%2C374%2C9%2C340-Franklin.png\" alt=\"R. Franklin\" width=\"130\" height=\"115\">\n" + " </div>\n" + " <div class=\"title\">R. Franklin</div>\n" + " </a>\n" + "</div>\n\n" + "<div class=\"category-gallery-item\">\n" + " <a href=\"/wiki/Jack_Colquitt\" title=\"Jack Colquitt\">\n" + " <div class=\"category-gallery-item-image\">\n" + " <img src=\"https://images.wikia.nocookie.net/__cb20121028070935/americanhorrorstory/images/thumb/4/46/Jack.png/130px-250%2C1119%2C0%2C768-Jack.png\" alt=\"Jack Colquitt\" width=\"130\" height=\"115\">\n" + " </div>\n" + " <div class=\"title\">Jack Colquitt</div>\n" + " </a>\n" + "</div>\n\n" + "<div class=\"category-gallery-item\">\n" + " <a href=\"/wiki/Dr._Hall\" title=\"Dr. Hall\">\n" + " <div class=\"category-gallery-item-image\">\n" + " <img src=\"https://images.wikia.nocookie.net/__cb20130122041507/americanhorrorstory/images/thumb/b/b4/Hall.png/130px-0%2C691%2C9%2C620-Hall.png\" alt=\"Dr. Hall\" width=\"130\" height=\"115\">\n" + " </div>\n" + " <div class=\"title\">Dr. Hall</div>\n" + " </a>\n" + "</div>\n\n" + "<div class=\"category-gallery-item\">\n" + " <a href=\"/wiki/Amir_Stanley\" title=\"Amir Stanley\">\n" + " <div class=\"category-gallery-item-image\">\n" + " <div class=\"snippet\">\n" + " <span class=\"quote\">“</span>\n" + " <span class=\"text\">REDIRECT Westfield High/Massacre#Amir Stanley This is a redirect from a character link. In other...</span>\n" + " </div>\n" + " </div>\n" + " <div class=\"title\">Amir Stanley</div>\n" + " </a>\n" + "</div>\n\n" + "<div class=\"category-gallery-item\">\n" + " <a href=\"/wiki/Angela_Harvey\" title=\"Angela Harvey\">\n" + " <div class=\"category-gallery-item-image\">\n" + " <div class=\"snippet\">\n" + " <span class=\"quote\">“</span>\n" + " <span class=\"text\">REDIRECT Lorraine Harvey#Angela Harvey This is a redirect from a character link. In other words...</span>\n" + " </div>\n" + " </div>\n" + " <div class=\"title\">Angela Harvey</div>\n" + " </a>\n" + "</div>\n\n" + "<div class=\"category-gallery-item\">\n" + " <a href=\"/wiki/Angie\" title=\"Angie\">\n" + " <div class=\"category-gallery-item-image\">\n" + " <div class=\"snippet\">\n" + " <span class=\"quote\">“</span>\n" + " <span class=\"text\">REDIRECT Piggy Piggy#Angie This is a redirect from a character link. In other words, this is a...</span>\n" + " </div>\n" + " </div>\n" + " <div class=\"title\">Angie</div>\n" + " </a>\n" + "</div>\n" + "</div>"; final String subst = "${title} https://vignette.wikia.nocookie.net/americanhorrorstory/images/${filepath}/revision/latest/"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE); final Matcher matcher = pattern.matcher(string); // The substituted value will be contained in the result variable final String result = matcher.replaceAll(subst); System.out.println("Substitution result: " + 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 Java, please visit: https://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html