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

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "gamers_online.*\\s*(\\d+),?(\\d+),?(\\d+)"; final String string = "[...]\n\n" + "<div id=\"about_header_area\" class=\" global\">\n" + " <div class=\"about_area_inner_wrapper\">\n" + " <div id=\"about_monitor_video\">\n" + " <video width=\"100%\" height=\"auto\" autoplay muted loop playsinline poster=\"https://cdn.fastly.steamstatic.com/store/about/videos/about_hero_loop_web.png\">\n" + " <source src=\"https://cdn.fastly.steamstatic.com/store/about/videos/about_hero_loop_web.webm\" type=\"video/webm\">\n" + " <source src=\"https://cdn.fastly.steamstatic.com/store/about/videos/about_hero_loop_web.mp4\" type=\"video/mp4\">\n" + " </video>\n" + " <div id=\"about_monitor_video_gradient\"></div>\n" + " </div>\n" + " <div id=\"about_header\">\n" + " <div id=\"about_greeting\">\n" + " <div class=\"about_greeting_header\">\n" + " <div class=\"steam_logo\"><img src=\"https://cdn.fastly.steamstatic.com/store//about/logo_steam.svg\" alt=\"The logo for Steam\"></div>\n" + " <div class=\"about_subtitle\">Steam is the ultimate destination for playing, discussing, and creating games.</div>\n" + " <div class=\"online_stats\">\n" + " <div class=\"online_stat\">\n" + " <div class=\"online_stat_label gamers_online\">online</div>\n" + " 36,426,658 </div>\n" + " <div class=\"online_stat\">\n" + " <div class=\"online_stat_label gamers_in_game\">playing now</div>\n" + " 10,289,777 </div>\n" + " </div>\n" + " </div>\n" + " \n" + " \n" + " <div class=\"about_install_wrapper\">\n" + " <div class=\"about_install win \">\n" + " <a href=\"https://cdn.fastly.steamstatic.com/client/installer/SteamSetup.exe\" class=\"about_install_steam_link\">Install Steam</a>\n" + " </div>\n" + " <div class=\"installer_list\">\n" + " <div class=\"available_platforms\">\n" + " Also available on:\n" + " </div>\n\n" + " <a class=\"platform_icon\" href=\"https://cdn.fastly.steamstatic.com/client/installer/steam.dmg\">\n" + " <img src=\"https://cdn.fastly.steamstatic.com/store/about/icon-macos.svg\">\n" + " </a>\n" + " <a class=\"platform_icon\" href=\"https://cdn.fastly.steamstatic.com/client/installer/steam.deb\">\n" + " <img src=\"https://cdn.fastly.steamstatic.com/store/about/icon-steamos.svg\">\n" + " </a>\n" + " <a class=\"platform_icon\" href=\"https://support.google.com/chromebook?p=steam_on_chromebook\">\n" + " <img src=\"https://cdn.fastly.steamstatic.com/store/about/icon-chromeos.svg\">\n" + " </a>\n" + " </div>\n" + " </div>\n" + " </div>\n" + " </div>\n" + " </div>\n" + " <div class=\"learn_more_btn\">\n" + " <a href=\"#about_games_cta_area\" class=\"smooth_scroll\">\n" + " Learn more <span class=\"down_arrow\"></span>\n" + " </a>\n" + " </div>\n" + "</div>\n"; final Pattern pattern = Pattern.compile(regex); final Matcher matcher = pattern.matcher(string); if (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