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

/
/
g

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 = "£\\d+\\.\\d{1,2}"; final String string = "<div style=\"float:left;\"><a class=\"url\" href=\"http://www.amazon.co.uk/AllThingsAccessory%C2%AE-Sports-Running-Jogging-... src=\"http://ecx.images-amazon.com/images/I/51bQWjrCioL._SL160_.jpg\" alt=\"AllThingsAccessory Sports\" border=\"0\" hspace=\"0\" vspace=\"0\" /></a></div><span class=\"riRssTitle\"><a href=\"http://www.amazon.co.uk/AllThingsAccessory%C2%AE-Sports-Running-Jogging-...® Sports Running Jogging Gym Armband Arm Band Case Cover Holder For iPhone 6 5 5S 5C 4S 4</a></span> <br /><span class=\"riRssContributor\">AllThingsAccessory®</span> <br /><img src=\"http://g-ecx.images-amazon.com/images/G/02/x-locale/common/icons/uparrow... width=\"13\" align=\"abstop\" alt=\"Ranking has gone up in the past 24 hours\" title=\"Ranking has gone up in the past 24 hours\" height=\"11\" border=\"0\" /> <font color=\"green\"><strong>52,006%</strong></font> Sales Rank in Sports & Outdoors: 50 (was 26,053 yesterday) <br /> <img src=\"http://g-ecx.images-amazon.com/images/G/02/detail/stars-4-5._V192253866_... width=\"64\" height=\"12\" border=\"0\" style=\"margin: 0; padding: 0;\"/>(51)<br /><br /><a href=\"http://www.amazon.co.uk/AllThingsAccessory%C2%AE-Sports-Running-Jogging-... new: </a> <strike>£7.99 - £9.99</strike> <font color=\"#990000\"><b>£4.99</b></font> <br /><br />(Visit the <a href=\"http://www.amazon.co.uk/gp/movers-and-shakers/sports/ref=pd_zg_rss_ms_sg... & Shakers in Sports & Outdoors</a> list for authoritative information on this product's current rank.)"; final Pattern pattern = Pattern.compile(regex); 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