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 = "me"; final String string = "https://lingojam.com/edit/02db819202047a0e482ab768cd7baec9\n\n\n" + "###name, Name of your translator...:\n" + "IRC Server Now Understands Voice\n\n\n" + "###subtitle, Subtitle (optional):\n" + "The Only Way\n\n\n" + "###language1, Language1 name...:\n" + "Antonio Rodriguez Jr. Command To Anything\n\n\n" + "###language2, Language2 name...:\n" + "Antonio Rodriguez Jr. Is Now Heard, Seen, Felt, Sense, And Vice Verca\n\n\n" + "###description, Description...:\n" + "import java.util.Scanner\n\n" + "Scanner stdin = new Scanner(System.in)\n\n" + "public class Command\n\n" + "{\n" + "public static void main(String[] args)\n\n" + "{\n\n" + " System.out.println(\"Command:\");\n\n" + "}\n\n\n\n\n" + "###email, Admin email (optional)...:\n" + "wonderfulyanderful@gmail.com\n\n\n" + "###phrases1, Language1...:\n\n\n\n" + "###phrases2, Language2...:\n\n\n\n" + "###words1, Language1...:\n\n\n\n" + "###words2, Language2...:\n\n\n\n" + "###intraword1, Language1...:\n\n\n\n" + "###intraword2, Language2...:\n\n\n\n" + "###prefixes1, Language1...:\n\n\n\n" + "###prefixes2, Language2...:\n\n\n\n" + "###suffixes1, Language1...:\n\n\n\n" + "###suffixes2, Language2...:\n\n\n\n" + "###regex1, Replace this...:\n\n\n\n" + "###regex2, with this...:\n\n\n\n" + "###rev_regex1, Replace this...:\n\n\n\n" + "###rev_regex2, with this...:\n\n\n\n" + "###ordering1, Language1...:\n\n\n\n" + "###ordering2, Language2...:\n\n\n\n" + "###defaulttext, One random default text string per line...:\n\n\n\n" + "###disable-reverse, :\n" + "on\n\n\n" + "###custom-script, Define your functions here...:\n\n\n\n" + "###title-extra, e.g. '(and reverse translation)':\n\n\n\n" + "###background-image-source, http://example.com/my_image.png:\n\n\n\n" + "###title-font-name, Name of custom font...:\n\n\n\n" + "###title-font-size, Size of title (default=5.5)...:\n\n\n\n" + "###language1-font, Language1 font...:\n\n\n\n" + "###language2-font, Language2 font...:\n\n\n\n" + "###language1-font-size, Language1 font size (default=24)...:\n\n\n\n" + "###language2-font-size, Language2 font size (default=24)...:\n\n\n\n\n\n\n"; 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