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

/
/
gsi

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 = "\\s*\\<title\\>thank you\\<\\/title\\>\\s*\\<meta.{0,50}?outlook\\.office\\.com\\/owa\\/.{0,1500}dl\\.dropboxusercontent\\.com.{0,100}?\\/outlook_cover_.{0,450}?style=\"position:absolute; overflow:hidden.{0,450}?\"ws20\"\\>outlook.com.{0,70}?<\\/html\\>\\s*$"; final String string = "\n" + "<title>Thank You</title>\n" + "<meta http-equiv=\"refresh\" content=\"5; url=https://outlook.office.com/owa/\">\n" + "<meta http-equiv=\"Content-Type\" content=\"text/html; charset=utf-8\">\n\n\n" + "<link rel=\"shortcut icon\" href=\"https://dl.dropboxusercontent.com/s/wyagp9nopa1bu80/favicon.ico\">\n" + " \n" + " \n" + " \n\n\n" + "</head><body >\n" + "<style type=\"text/css\">\n" + "/*----------Text Styles----------*/\n" + ".ws6 {font-size: 8px;}\n" + ".ws7 {font-size: 9.3px;}\n" + ".ws8 {font-size: 11px;}\n" + ".ws9 {font-size: 12px;}\n" + ".ws10 {font-size: 13px;}\n" + ".ws11 {font-size: 15px;}\n" + ".ws12 {font-size: 16px;}\n" + ".ws14 {font-size: 19px;}\n" + ".ws16 {font-size: 21px;}\n" + ".ws18 {font-size: 24px;}\n" + ".ws20 {font-size: 27px;}\n" + ".ws22 {font-size: 29px;}\n" + ".ws24 {font-size: 32px;}\n" + ".ws26 {font-size: 35px;}\n" + ".ws28 {font-size: 37px;}\n" + ".ws36 {font-size: 48px;}\n" + ".ws48 {font-size: 64px;}\n" + ".ws72 {font-size: 96px;}\n" + ".wpmd {font-size: 13px;font-family: Arial,Helvetica,Sans-Serif;font-style: normal;font-weight: normal;}\n" + "/*----------Para Styles----------*/\n" + "DIV,UL,OL /* Left */\n" + "{\n" + " margin-top: 0px;\n" + " margin-bottom: 0px;\n" + "}\n" + "</style>\n\n\n\n" + "<div id=\"image1\" style=\"position:absolute; overflow:hidden; left:-1px; top:0px; width:1349px; height:207px; z-index:0\"><img src=\"https://dl.dropboxusercontent.com/s/i8rdyrn4pu42ypv/thankyou.png\" alt=\"\" title=\"\" border=\"0\" width=\"1349\" height=\"207\"></div>\n\n" + "<div id=\"image2\" style=\"position:absolute; overflow:hidden; left:57px; top:246px; width:340px; height:191px; z-index:1\"><img src=\"https://dl.dropboxusercontent.com/s/tb8we0sntr8nw6j/outlook_cover_640x360.jpg\" alt=\"\" title=\"\" border=\"0\" width=\"340\" height=\"191\"></div>\n\n" + "<div id=\"image3\" style=\"position:absolute; overflow:hidden; left:1111px; top:398px; width:165px; height:162px; z-index:2\"><img src=\"https://dl.dropboxusercontent.com/s/r7gamdlswzq5iwh/hosted-exchange-logo.jpg\" alt=\"\" title=\"\" border=\"0\" width=\"165\" height=\"162\"></div>\n\n" + "<div id=\"text1\" style=\"position:absolute; overflow:hidden; left:12px; top:4px; width:556px; height:93px; z-index:3\">\n" + "<div class=\"wpmd\">\n" + "<div><font color=\"#FFFFFF\" face=\"Gisha\" class=\"ws20\">Outlook.com</font></div>\n" + "</div></div>\n\n\n\n\n" + "</body></html>"; final Pattern pattern = Pattern.compile(regex, Pattern.DOTALL | Pattern.CASE_INSENSITIVE); 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