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 = "<(?!\\/*strong\\W|\\/*h1\\W|\\/*input\\W|\\/*b\\W).*?>"; final String string = "<form action=\"#\" method=\"post\">\n" + " <div>\n" + " <label for=\"name\">Text Input:</label>\n" + " <input type=\"text\" name=\"name\" id=\"name\" value=\"\" tabindex=\"1\" />\n" + " </div>\n\n" + " <div>\n" + " <h4>Radio Button Choice</h4>\n\n" + " <label for=\"radio-choice-1\">Choice 1</label>\n" + " <input type=\"radio\" name=\"radio-choice-1\" id=\"radio-choice-1\" tabindex=\"2\" value=\"choice-1\" />\n\n" + " <label for=\"radio-choice-2\">Choice 2</label>\n" + " <input type=\"radio\" name=\"radio-choice-2\" id=\"radio-choice-2\" tabindex=\"3\" value=\"choice-2\" />\n" + " </div>\n\n" + " <div>\n" + " <label for=\"select-choice\">Select Dropdown Choice:</label>\n" + " <select name=\"select-choice\" id=\"select-choice\">\n" + " <option value=\"Choice 1\">Choice 1</option>\n" + " <option value=\"Choice 2\">Choice 2</option>\n" + " <option value=\"Choice 3\">Choice 3</option>\n" + " </select>\n" + " </div>\n\n" + " <div>\n" + " <label for=\"textarea\">Textarea:</label>\n" + " <textarea cols=\"40\" rows=\"8\" name=\"textarea\" id=\"textarea\"></textarea>\n" + " </div>\n\n" + " <div>\n" + " <label for=\"checkbox\">Checkbox:</label>\n" + " <input type=\"checkbox\" name=\"checkbox\" id=\"checkbox\" />\n" + " </div>\n\n" + " <div>\n" + " <input type=\"submit\" value=\"Submit\" />\n" + " </div>\n" + "</form>"; 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