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 = "(?si)\\A\\s*(?:(<!--.*?-->|<!DOCTYPE\\s+svg([\\s:]+.*?>|>))\\s*)*<svg[\\s>\\/]"; final String string = "<!-- test -->\n\n" + "some <p></p> html tags, this svg file is not valid\n\n" + "also, look after </svg> ends\n\n" + " <!-- prettier-ignore -->\n" + " <svg xmlns=\"http://www.w3.org/2000/svg\" width=\"10\" height=\"10\" viewBox=\"0 0 10 10\">\n" + " <path fill=\"#8E8E93\" fill-rule=\"evenodd\" d=\"M9.816 8.981L7.08 6.243c.49-.67.753-1.479.75-2.309C7.819 1.767 6.067.013 3.9 0 2.864-.005 1.868.406 1.135 1.14.403 1.872-.006 2.868 0 3.905.01 6.072 1.762 7.828 3.93 7.84c.833.004 1.645-.262 2.315-.758l.003-.002 2.735 2.736c.148.156.368.218.576.165.207-.054.37-.216.423-.424.054-.207-.01-.428-.165-.576zm-5.89-1.925C2.193 7.046.79 5.642.783 3.909c-.005-.83.322-1.626.908-2.213.586-.587 1.383-.915 2.212-.912 1.733.01 3.135 1.414 3.143 3.147.004.83-.323 1.626-.909 2.213-.586.587-1.382.915-2.211.912z\"/>\n" + " </svg>\n" + " <svg xmlns=\"http://www.w3.org/2000/svg\" width=\"10\" height=\"10\" viewBox=\"0 0 10 10\"><path fill=\"#8E8E93\" fill-rule=\"evenodd\" d=\"M9.816 8.981L7.08 6.243c.49-.67.753-1.479.75-2.309C7.819 1.767 6.067.013 3.9 0 2.864-.005 1.868.406 1.135 1.14.403 1.872-.006 2.868 0 3.905.01 6.072 1.762 7.828 3.93 7.84c.833.004 1.645-.262 2.315-.758l.003-.002 2.735 2.736c.148.156.368.218.576.165.207-.054.37-.216.423-.424.054-.207-.01-.428-.165-.576zm-5.89-1.925C2.193 7.046.79 5.642.783 3.909c-.005-.83.322-1.626.908-2.213.586-.587 1.383-.915 2.212-.912 1.733.01 3.135 1.414 3.143 3.147.004.83-.323 1.626-.909 2.213-.586.587-1.382.915-2.211.912z\"/></svg>\n" + " </div>\n\n" + " <button class=\"product-list-filter__reset\" type=\"button\">\n" + "@ -49,9 +50,10 @@\n" + " <div class=\"product-list-filter__scrollable\">\n" + " <div class=\"js-namings-autocomplete-matched\">\n" + " @foreach ($filter_namings->sortBy('display_name') as $naming)\n" + " @continue($search_namings->contains('display_name', $naming->display_name))\n" + " <div class=\"spoiler__item\">\n" + " <label tabindex=\"0\">\n" + " <input type=\"checkbox\" value=\"{{ $naming->id }}\" {{ $search_namings->contains($naming->display_name) ? 'data-checked=\"true\"' : 'data-checked=\"false\"' }}>\n" + " <input type=\"checkbox\" value=\"{{ $naming->id }}\" {!! $search_namings->contains('display_name', $naming->display_name) ? 'data-checked=\"true\"' : 'data-checked=\"false\"' !!}>\n" + " <span>{{ $naming->display_name }}</span>\n" + " </label>\n" + " </div>"; 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