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

/
/
gmi

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 = "^[\\s\\u00A9\\u00AE\\u203C\\u2049\\u2122\\u2139\\u2194-\\u2199\\u21A9-\\u21AA\\u231A-\\u231B\\u2328\\u23CF\\u23E9-\\u23F3\\u23F8-\\u23FA\\u24C2\\u25AA-\\u25AB\\u25B6\\u25C0\\u25FB-\\u25FE\\u2600-\\u2604\\u260E\\u2611\\u2614-\\u2615\\u2618\\u261D\\u2620\\u2622-\\u2623\\u2626\\u262A\\u262E-\\u262F\\u2638-\\u263A\\u2648-\\u2653\\u2660\\u2663\\u2665-\\u2666\\u2668\\u267B\\u267F\\u2692-\\u2694\\u2696-\\u2697\\u2699\\u269B-\\u269C\\u26A0-\\u26A1\\u26AA-\\u26AB\\u26B0-\\u26B1\\u26BD-\\u26BE\\u26C4-\\u26C5\\u26C8\\u26CE-\\u26CF\\u26D1\\u26D3-\\u26D4\\u26E9-\\u26EA\\u26F0-\\u26F5\\u26F7-\\u26FA\\u26FD\\u2702\\u2705\\u2708-\\u270D\\u270F\\u2712\\u2714\\u2716\\u271D\\u2721\\u2728\\u2733-\\u2734\\u2744\\u2747\\u274C\\u274E\\u2753-\\u2755\\u2757\\u2763-\\u2764\\u2795-\\u2797\\u27A1\\u27B0\\u27BF\\u2934-\\u2935\\u2B05-\\u2B07\\u2B1B-\\u2B1C\\u2B50\\u2B55\\u3030\\u303D\\u3297\\u3299\\u1F004\\u1F0CF\\u1F170-\\u1F171\\u1F17E-\\u1F17F\\u1F18E\\u1F191-\\u1F19A\\u1F201-\\u1F202\\u1F21A\\u1F22F\\u1F232-\\u1F23A\\u1F250-\\u1F251\\u1F300-\\u1F321\\u1F324-\\u1F393\\u1F396-\\u1F397\\u1F399-\\u1F39B\\u1F39E-\\u1F3F0\\u1F3F3-\\u1F3F5\\u1F3F7-\\u1F4FD\\u1F4FF-\\u1F53D\\u1F549-\\u1F54E\\u1F550-\\u1F567\\u1F56F-\\u1F570\\u1F573-\\u1F579\\u1F587\\u1F58A-\\u1F58D\\u1F590\\u1F595-\\u1F596\\u1F5A5\\u1F5A8\\u1F5B1-\\u1F5B2\\u1F5BC\\u1F5C2-\\u1F5C4\\u1F5D1-\\u1F5D3\\u1F5DC-\\u1F5DE\\u1F5E1\\u1F5E3\\u1F5EF\\u1F5F3\\u1F5FA-\\u1F64F\\u1F680-\\u1F6C5\\u1F6CB-\\u1F6D0\\u1F6E0-\\u1F6E5\\u1F6E9\\u1F6EB-\\u1F6EC\\u1F6F0\\u1F6F3\\u1F910-\\u1F918\\u1F980-\\u1F984\\u1F9C0\\}]+$"; final String string = "Test with Unicode עברית\n" + "Test with Unicode and Emoji ? עברית\n"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE | Pattern.CASE_INSENSITIVE); 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