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 = "^(([a-zA-Z0-9\\|\\!\\._\\-\\s\\:]*<a href=\\\"#\\\" onclick=\\\"ON_CLICK_EVENT\\\">[a-zA-Z0-9\\|\\!\\._\\-]*<\\/a>)|(<a href=\\\"#\\\" on(c|C)lick=\\\"(HSBC_pre_chat_est\\(\\)\\;\\s)*ON_CLICK_EVENT\\\"(\\s)*>(\\s)*<img src=(\\'|\\\")[a-zA-Z0-9\\|\\!\\._\\-\\:\\,\\/\\s]*(\\'|\\\")(\\s)*(\\/)*>(\\s)*<\\/a>)|(<a href=\\\"#\\\" onclick='try \\{ LPButtonClicked\\(\\)\\; \\} catch \\(e\\) \\{\\}\\; ON_CLICK_EVENT'\\; title=\\\"Start Live Chat\\\"><img src=\\\"[a-zA-Z0-9\\|\\!\\._\\-\\:\\,\\/\\s]*\\\" border=0 alt=\\\"Live Chat\\\" onload=\\\"LPButtonDisplayed\\(\\)\\\"><\\/a>)|([a-zA-Z0-9\\|\\!\\._\\-\\s]*<a href=\\\"#\\\" onclick=(\\'|\\\")ON_CLICK_EVENT(\\'|\\\")><span><span class=\\\"lpStartChat\\\">[a-zA-Z0-9\\|\\!\\._\\-\\s]*<\\/span><\\/span><\\/a>)|(<a href='javascript\\:\\;' on(c|C)lick='javascript\\:ON_CLICK_EVENT\\;'>(\\s)*<img src='[a-zA-Z0-9\\|\\!\\._\\-\\:\\,\\/\\s]*'(\\s)*(border='0'\\salt='Chat with an HSBC Representative' title='Chat with an HSBC Representative')*(\\/)*>(\\s)*<\\/a>)|(<a href='#' onClick='javascript\\:ON_CLICK_EVENT\\; '>[a-zA-Z0-9\\|\\!\\._\\-\\s]*<\\/a>)|(<h4>Live Chat<\\/h4>(\\s)*<div class=\\\"supportContentGeneralBoxInnerChat\\\">(\\s)*<h5>Welcome to Live Chat<\\/h5>(\\s)*<p>How can we help you\\?<\\/p>(\\s)*<p><a class=\\\"redBtn liveChatBtn\\\" href=\\\"#\\\"(\\s)*onclick=\\\"ON_CLICK_EVENT\\\" title=\\\"Start Chat\\\"><span>Start Chat<\\/span><\\/a><\\/p>(\\s)*<\\/div>)|(<div style='padding\\:0px' box-shadow\\: -3px 3px 10px(\\s)*#888888\\;><a href=\\\"#\\\" onClick='ON_CLICK_EVENT\\;'target=\\\"_self\\\">(\\s)*<img src='[a-zA-Z0-9\\|\\!\\._\\-\\:\\,\\/\\s]*'(\\s)*id='SwitchButton' Border='0'\\/><\\/a><\\/div>)|(<div id=\\\"lpButtonTab\\\" style=\\\"float:left; width:30px\\\" onclick=\\\"lpStickyButton\\.toggleState\\(\\);\\\"><img src=\\\"[a-zA-Z0-9\\|\\!\\._\\-\\:\\,\\/\\s]*\\\" width=\\\"30\\\" height=\\\"125\\\" border=\\\"0\\\" \\/><\\/div>(\\s)*<div id=\\\"lpButtonArea\\\" style=\\\"margin-left:30px; width:251px\\\"><img src='[a-zA-Z0-9\\|\\!\\._\\-\\:\\,\\/\\s]*' style='cursor:pointer' onclick='ON_CLICK_EVENT' \\/><\\/div>)|(<div class=\\\"liveChatSideBox\\\">(\\s)*<h2>Live chat<\\/h2>(\\s)*<p>Welcome to Live Chat\\. How can we help you\\?<\\/p>(\\s)*<p><a class=\\\"redBtn liveChatBtn\\\" href=\\\"#\\\"(\\s)*onclick=\\\"ON_CLICK_EVENT\\\"(\\s)*title=\\\"Start Chat\\\"><span>Start Chat<\\/span><\\/a><\\/p>(\\s)*<\\/div>))$"; final String string = "<div class=\"liveChatSideBox\">\n" + " <h2>Live chat</h2>\n" + " <p>Welcome to Live Chat. How can we help you?</p>\n" + " <p><a class=\"redBtn liveChatBtn\" href=\"#\" onclick=\"ON_CLICK_EVENT\"\n" + "title=\"Start Chat\"><span>Start Chat</span></a></p> </div>\n\n" + "<a href=\"#\" onclick=\"ON_CLICK_EVENT\" >\n" + "<img src='https://www.hsbc.co.uk/content_static/en/images/en/alt_design_3E.png' />\n" + "</a>"; 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