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

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "File size.*?<span[^>]*>(\\d+\\.?\\d*\\s*[KMG]B)<\\/span>"; final String string = "<div id=\"morpheusDesktopCelwidget\" class=\"a-section a-spacing-none celwidget\"><div id=\"bfae-desktop-main-content\" class=\"a-section a-spacing-large celwidget sidesheetWidget\"><div id=\"morpheus-header\" class=\"a-row _bW9yc_header-sticky_3psnt\"><div id=\"morpheus-header-title\" class=\"a-section a-spacing-none\"><div class=\"a-row _bW9yc_title-row_1ABR4 _bW9yc_sticky-header-title_3xWoM\" dir=\"auto\"><div class=\"a-column a-span6 _bW9yc_title-column_11SVA\"><h1 id=\"morpheus-heading-title\" class=\"a-size-base a-text-bold\" dir=\"auto\">5 formats &amp; editions</h1></div><div class=\"a-column a-span6 a-text-right _bW9yc_title-column_11SVA a-span-last\"><span class=\"a-declarative\" data-action=\"a-popover\" data-csa-c-type=\"widget\" data-csa-c-func-deps=\"aui-da-a-popover\" data-a-popover=\"{&quot;position&quot;:&quot;triggerBottom&quot;,&quot;inlineContent&quot;:&quot;Results are primarily sorted by price&quot;,&quot;closeButton&quot;:&quot;true&quot;}\"><a href=\"javascript:void(0)\" role=\"button\" class=\"a-popover-trigger a-declarative\">How are results ordered?<i class=\"a-icon a-icon-popover\"></i></a></span></div></div></div><hr aria-hidden=\"true\" class=\"a-spacing-none a-divider-normal _bW9yc_custom-divider_2qkyu\"/><div id=\"morpheus-header-formats\" class=\"a-section a-spacing-none\"><div class=\"a-section a-spacing-base a-spacing-top-base _bW9yc_formats-scroller_2YNW7\"><tags-scroller id=\"formats\" tags=\"[{&quot;name&quot;:&quot;Kindle (1)&quot;,&quot;selected&quot;:true,&quot;id&quot;:&quot;kindle_meta_binding&quot;,&quot;reference&quot;:&quot;/api/marketplaces/ATVPDKIKX0DER/products/B07P1QTM2P/book-formats-and-editions?selectedFormats=%5B%22kindle_meta_binding%22%5D&quot;},{&quot;name&quot;:&quot;Audiobook (1)&quot;,&quot;selected&quot;:false,&quot;id&quot;:&quot;audiobooks_digital_meta_binding&quot;,&quot;reference&quot;:&quot;/api/marketplaces/ATVPDKIKX0DER/products/B07QFSM4RJ/book-formats-and-editions?selectedFormats=%5B%22audiobooks_digital_meta_binding%22%5D&quot;},{&quot;name&quot;:&quot;Hardcover (1)&quot;,&quot;selected&quot;:false,&quot;id&quot;:&quot;hardcover_meta_binding&quot;,&quot;reference&quot;:&quot;/api/marketplaces/ATVPDKIKX0DER/products/1945051639/book-formats-and-editions?selectedFormats=%5B%22hardcover_meta_binding%22%5D&quot;},{&quot;name&quot;:&quot;Paperback (1)&quot;,&quot;selected&quot;:false,&quot;id&quot;:&quot;paperback_meta_binding&quot;,&quot;reference&quot;:&quot;/api/marketplaces/ATVPDKIKX0DER/products/1945051825/book-formats-and-editions?selectedFormats=%5B%22paperback_meta_binding%22%5D&quot;},{&quot;name&quot;:&quot;Spiral-bound (1)&quot;,&quot;selected&quot;:false,&quot;id&quot;:&quot;spiral_bound_meta_binding&quot;,&quot;reference&quot;:&quot;/api/marketplaces/ATVPDKIKX0DER/products/B08GHD27JR/book-formats-and-editions?selectedFormats=%5B%22spiral_bound_meta_binding%22%5D&quot;}]\" data-mix-operations=\"formatPillClickHandler\" selectionmode=\"single\"><input type=\"hidden\" name=\"\" value=\"/api/marketplaces/ATVPDKIKX0DER/products/B07P1QTM2P/book-formats-and-editions?selectedFormats=%5B%22kindle_meta_binding%22%5D\" id=\"kindle_meta_binding-formatReference\"/><input type=\"hidden\" name=\"\" value=\"/api/marketplaces/ATVPDKIKX0DER/products/B07QFSM4RJ/book-formats-and-editions?selectedFormats=%5B%22audiobooks_digital_meta_binding%22%5D\" id=\"audiobooks_digital_meta_binding-formatReference\"/><input type=\"hidden\" name=\"\" value=\"/api/marketplaces/ATVPDKIKX0DER/products/1945051639/book-formats-and-editions?selectedFormats=%5B%22hardcover_meta_binding%22%5D\" id=\"hardcover_meta_binding-formatReference\"/><input type=\"hidden\" name=\"\" value=\"/api/marketplaces/ATVPDKIKX0DER/products/1945051825/book-formats-and-editions?selectedFormats=%5B%22paperback_meta_binding%22%5D\" id=\"paperback_meta_binding-formatReference\"/><input type=\"hidden\" name=\"\" value=\"/api/marketplaces/ATVPDKIKX0DER/products/B08GHD27JR/book-formats-and-editions?selectedFormats=%5B%22spiral_bound_meta_binding%22%5D\" id=\"spiral_bound_meta_binding-formatReference\"/></tags-scroller></div><hr aria-hidden=\"true\" class=\"a-spacing-none a-divider-normal\"/></div></div><div id=\"kindle_meta_binding\" class=\"a-row _bW9yc_pill-content_2rpOw\"><div class=\"sidesheetAsinListContainer\" id=\"morpheus-asin-list\"><div class=\"a-section editions-container\"><div class=\"_bW9yc_item_138i_\"><div class=\"a-section a-spacing-none _bW9yc_edition-item_1KJ__\"><input type=\"hidden\" value=\"B07P1QTM2P\" aria-hidden=\"true\"/><div class=\"a-row _bW9yc_asin-upper-section_1r6w9\"><div class=\"a-column a-span2\"><div data-mix-operations=\"editionClickHandler\"><a aria-hidden=\"true\" aria-label=\"Starting a Business QuickStart Guide: The Simplified Beginner’s Guide to Launching a Successful Small Business, Turning Your Vision into Reality, and Achieving ... (Starting a Business - QuickStart Guides)\" class=\"a-size-mini a-spacing-mini a-spacing-top-micro a-link-normal _bW9yc_img-link_3-kr7\" tabindex=\"-1\" href=\"/Starting-Business-QuickStart-Guide-Entrepreneurial-ebook/dp/B07P1QTM2P/ref=monarch_sidesheet_image\"><img alt=\"\" src=\"https://m.media-amazon.com/images/I/71e3axVLfNL._AC_.jpg\" aria-hidden=\"true\" class=\"_bW9yc_cover_22Xe6\"/></a></div></div><div class=\"a-column a-span10 a-span-last\"><div data-mix-operations=\"editionClickHandler\"><h2 id=\"asinItemTitleB07P1QTM2P\" class=\"a-size-base a-text-bold\"><a class=\"a-spacing-mini a-spacing-top-micro a-link-normal _bW9yc_link_1JCGH\" href=\"/Starting-Business-QuickStart-Guide-Entrepreneurial-ebook/dp/B07P1QTM2P/ref=monarch_sidesheet_title\">Starting a Business QuickStart Guide: The Simplified Beginner’s Guide to Launching a Successful Small Business, Turning Your Vision into Reality, and Achieving ... (Starting a Business - QuickStart Guides)</a></h2></div></div><div class=\"a-column a-span10 a-span-last\"><div class=\"a-section a-spacing-top-small _bW9yc_offer-section_3KU5H\"><div class=\"a-section a-spacing-none _bW9yc_price-section_1ormK\"><span class=\"a-price\" data-a-size=\"xl\" data-a-color=\"base\"><span class=\"a-offscreen\">$15.49</span><span aria-hidden=\"true\"><span class=\"a-price-symbol\">$</span><span class=\"a-price-whole\">15<span class=\"a-price-decimal\">.</span></span><span class=\"a-price-fraction\">49</span></span></span></div></div></div></div><hr aria-hidden=\"true\" class=\"a-spacing-medium a-spacing-top-small a-divider-normal\"/><div class=\"a-section\"><div class=\"a-row\"><dl class=\"a-definition-list a-vertical _bW9yc_metadata-sec_1pdTz\" role=\"presentation\"><div class=\"a-column a-span12 a-spacing-none\"><div class=\"a-row\"><div class=\"a-column a-span6 a-spacing-none\"><dt class=\"a-list-item\"><span class=\"a-size-small\">Edition</span></dt></div><div class=\"a-column a-span6 a-spacing-none a-span-last\"><dd class=\"a-list-item\"><span class=\"a-size-small\">1</span></dd></div></div></div><div class=\"a-column a-span12 a-spacing-none\"><div class=\"a-row\"><div class=\"a-column a-span6 a-spacing-none\"><dt class=\"a-list-item\"><span class=\"a-size-small\">Print length</span></dt></div><div class=\"a-column a-span6 a-spacing-none a-span-last\"><dd class=\"a-list-item\"><span class=\"a-size-small\">434 pages</span></dd></div></div></div><div class=\"a-column a-span12 a-spacing-none\"><div class=\"a-row\"><div class=\"a-column a-span6 a-spacing-none\"><dt class=\"a-list-item\"><span class=\"a-size-small\">Publication date</span></dt></div><div class=\"a-column a-span6 a-spacing-none a-span-last\"><dd class=\"a-list-item\"><span class=\"a-size-small\">February 24, 2019</span></dd></div></div></div><div class=\"a-column a-span12 a-spacing-none\"><div class=\"a-row\"><div class=\"a-column a-span6 a-spacing-none\"><dt class=\"a-list-item\"><span class=\"a-size-small\">File size</span></dt></div><div class=\"a-column a-span6 a-spacing-none a-span-last\"><dd class=\"a-list-item\"><span class=\"a-size-small\">4.3 MB</span></dd></div></div></div></dl></div></div></div><hr aria-hidden=\"true\" class=\"a-divider-normal _bW9yc_divider_3EwUq\"/></div></div><div class=\"a-section a-spacing-none kindle_meta_binding_pagination_container\"></div></div></div><div id=\"audiobooks_digital_meta_binding\" class=\"a-row _bW9yc_pill-content_2rpOw\"></div><div id=\"hardcover_meta_binding\" class=\"a-row _bW9yc_pill-content_2rpOw\"></div><div id=\"paperback_meta_binding\" class=\"a-row _bW9yc_pill-content_2rpOw\"></div><div id=\"spiral_bound_meta_binding\" class=\"a-row _bW9yc_pill-content_2rpOw\"></div></div></div>\n"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE); final Matcher matcher = pattern.matcher(string); while (matcher.find()) { System.out.println("Full match: " + matcher.group(0)); for (int i = 1; i <= matcher.groupCount(); i++) { System.out.println("Group " + i + ": " + matcher.group(i)); } } } }

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