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 = "(^\\|(?<tableSeparator>[\\s\\-|]+)\\|\\n)|(^\\|\\s*(?<tableTopFirst>[^|]+)(?=.*\\n\\|\\s*-))|((?<!^)\\|(?<tableTopMiddle>[^|\\n]+)(?=\\|.*\\|\\n\\| -))|(\\|(?<tableTopLast>[^|]+)\\|\\n(?=\\|\\s*-))|(^\\|\\s*(?<tableBottomFirst>[^|]+)(?=.*\\n^[^|]))|((?<!^)\\|(?<tableBottomMiddle>[^|\\n]+)(?=\\|.*\\|\\n[^|]))|(\\|\\s*(?<tableBottomLast>[^|]+)\\|\\n(?!\\|))|(^\\|\\s*(?<tableMiddleFirst>[^|]+)(?=\\|))|(\\|\\s*(?<tableMiddleLast>[^|]+)\\|\\n)|(\\|\\s*(?<tableMiddleMiddle>[^|]+))|!?(\\[(?<text>[^(]+)]\\((?<url>[^\")]+))(\"(?<title>[^\"]+)\"|.*)\\)|((?<!-.+\\n)- (?<unorderedListFirstItem>.+)\\n)|((?<=-.+\\n)- (?<unorderedListMiddleItem>.+)\\n(?=-))|(- (?<unorderedListLastItem>.+)\\n(?!-))|((?<!\\d+\\..+\\n)\\d+\\. (?<orderedListFirstItem>.+)\\n)|((?<=\\d+\\..+\\n)\\d+\\. (?<orderedListMiddleItem>.+)\\n(?=\\d+\\.))|(\\d+\\. (?<orderedListLastItem>.+)\\n(?!\\d+\\.))|(\\*\\*\\*(?<boldAndItalic>[^*]*)\\*\\*\\*)|(\\*\\*(?<bold>[^*]*)\\*\\*)|(\\*(?<italic>[^*]*)\\*)|(~~(?<strikethrough>[^~]*)~~)|(`{3}\\n(?<multilineCode>[^`]+)`{3}\\n)|(`(?<inlineCode>[^`\\n]*)`)|(^#{6} (?<h6>.+))|(^#{5} (?<h5>.+))|(^#{4} (?<h4>.+))|(^#{3} (?<h3>.+))|(^#{2} (?<h2>.+))|(^# (?<h1>.+))|(?<horizontalLine>^-{3}\\n)|(?<=^\\n)> (?<singleLineQuote>.+)\\n(?!^>)|((?<!> .+\\n)> (?<quoteFirst>.+))|(> (?<quoteLast>.+)(?!.*\\n> .+))|(> (?<quoteMiddle>.+))|(?<lineBreak>\\n{2})"; final String string = "# Table\n" + "| Syntax test | Description | Test | XXX | XXX |\n" + "| ----------- | ----------- | ---- | --- | --- |\n" + "| Header | Title | AAAA | XXX | XXX |\n" + "| Header | Title | AAAA | XXX | XXX |\n" + "| Paragraph | Text | BBBB | XXX | XXX |\n\n" + "## Pretty table\n" + "|Header 1|Header 2|\n" + "|---|---|\n" + "|![Kitty](https://placekitten.com/200/300 \"Kitten\")|![Kitty](https://placekitten.com/200/300? \"Kitten\")|\n\n" + "### Lists\n" + "---\n\n" + "- Inline *code* `aaaaz`\n" + "- My **favorite search** engine is ~~not~~ [Duck Duck Go](https://duckduckgo.com \"Click me\").\n" + "- ~~***Recursive***~~\n" + "- ***~~Recursive reversed~~***\n" + "- Item 4\n\n" + "1. Item\n" + "2. Item\n" + "3. Item\n" + "4. Item\n\n" + "1. c\n" + "1. c\n\n" + "#### Multiline code\n" + "```\n" + "int method() {\n" + " return 2137;\n" + "}\n" + "```\n\n" + "##### Quotes\n" + "> aa\n" + "> aa\n" + "> > bb\n" + "> > bb\n" + "> > > [c](#panes)c\n" + "> > > cc\n" + "> > bb\n" + "> > bb\n" + "> aa\n" + "> aa\n\n" + "> single line\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