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

r"
"
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|O|0|3|\\}|>|\\*\\<\\||\\|)?(%|#|\\||x|X|B|8|:|;|\\=)('|\")?(\\^|c|-|‑|o|っ)?(D|\\)|\\(|c|<|\\[|\\]|C|\\{|\\}|\\||\\&|>|\\||3|Þ|þ|b|p|P|o|O|J|L|S|s|X|\\\\|\\.|/|\\$|\\*|#|@))"; final String string = ":( Hello!\n" + "Howdy :)!\n" + "Are you there :P?\n" + "I'm fine :)\n" + ":p\n" + ":O\n" + ":3\n" + ":|\n" + ":/\n" + ":\\\n" + ":$\n" + ":*\n" + ":@\n" + ":(\n\n" + ":-(\n" + ":-)\n" + ":-P\n" + ":-p\n" + ":-O\n" + ":-3\n" + ":-|\n" + ":-/\n" + ":-\\\n" + ":-$\n" + ":-*\n" + ":-@\n\n" + ":^(\n" + ":^)\n" + ":^P\n" + ":^p\n" + ":^O\n" + ":^3\n" + ":^|\n" + ":^/\n" + ":^\\\n" + ":^$\n" + ":^*\n" + ":^@\n\n" + "):\n" + "(:\n" + "$:\n" + "*:\n\n" + ")-:\n" + "(-:\n" + "$-:\n" + "*-:\n\n" + ")^:\n" + "(^:\n" + "$^:\n" + "*^:\n\n" + "<3\n" + "</3\n" + "<\\3\n\n" + ":‑) \n" + ":) \n" + ":D \n" + ":o) \n" + ":-)\n" + ":] \n" + ":3 \n" + ":c) \n" + ":> \n" + ":-&\n" + "=] \n" + "8) \n" + "=) \n" + ":} \n" + ":^) \n" + ":‑D \n" + "8‑D \n" + "8D \n" + "x‑D \n" + "xD \n" + "X‑D\n" + "XD \n" + "=‑D \n" + "=D \n" + "=‑3 \n" + "=3 \n" + "B^D\n" + ":-))\n" + ">:[ \n" + ":‑( \n" + ":( \n" + ":‑c\n" + ":c \n" + ":-< \n" + ":っC \n" + ":< \n" + ":-< \n" + ":‑[ \n" + ":[ \n" + ":{\n" + ";(\n" + ":-|| \n" + ":@ \n" + ">:(\n" + ":'‑( \n" + ":\"(\n" + ":\"-(\n" + ":'(\n" + ":'‑) \n" + ":')\n" + "D:< \n" + "D: \n" + "D8 \n" + "D; \n" + "D= \n" + "DX \n" + "v.v \n" + "D‑':\n" + ":'-D\n" + ">:O \n" + ":‑O \n" + ":O \n" + ":‑o \n" + ":o \n" + "8‑0 \n" + "O_O \n" + "o‑o \n" + "O_o \n" + "o_O \n" + "o_o\n" + "owo\n" + "Owo\n" + "OwO\n" + "ouo\n" + "OuO \n" + "O-O\n" + ":* \n" + ":^*\n" + ";‑)\n" + ";)\n" + ";‑] \n" + ";]\n" + ";D\n" + ";^)\n" + ">:P\n" + ":‑P \n" + ":P \n" + "X‑P \n" + "x‑p \n" + "xp \n" + "XP \n" + ":‑p \n" + ":p \n" + "=p \n" + ":‑Þ \n" + ":Þ \n" + ":þ \n" + ":‑þ \n" + ":‑b \n" + ":b \n" + "d:\n" + ">:\\\n" + ">:/\n" + ":‑/\n" + ":‑.\n" + ":/\n" + ":\\\n" + ":L\n" + "=/\n" + "=\\\n" + ":L\n" + "=L\n" + ":S\n" + ">.<\n" + ">/<\n" + ">//<\n" + ">///<\n" + ":|\n" + ":‑|\n" + ":$\n" + ":‑X\n" + ":X\n" + ":‑#\n" + ":#\n" + "O:‑)\n" + "0:‑3 \n" + "0:3 \n" + "0:‑) \n" + "0:) \n" + "0;^)\n" + ">:)\n" + ">;)\n" + ">:‑)\n" + "}:‑)\n" + "}:)\n" + "3:‑)\n" + "3:)\n" + ">_>\n" + "^ ^\n" + "^_^\n" + "^_<\n" + ">_^\n" + "<_<\n" + "|;-)\n" + "|-O\n" + ":-J\n" + ":-&\n" + ":&\n" + "#-)\n" + "#)\n" + "%-)\n" + "%)\n" + ":|\n\n" + ":o|\n" + ":-|\n" + "ಠ_ಠ\n" + ":-\\\n" + "*<|:-)\n" + "<3 </3\n" + "ˊ_>ˋ\n"; 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