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

/
/
mgx

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 = "^ # begin\n" + "\\s*# some empty spaces\n" + "(?:\n" + " \\+? # + symbol\n" + " \\d{1,2} # country code\n" + " \\s*\n" + " (?(?=\\)) # if followed by parens\n" + " | # then dash not allowed\n" + " -? # else optional dash\n" + " )\n" + ")? #prefix like +380\n" + "\\s*\n" + "(?: \n" + " (?P<leftparen>\\()? # optional left paren\n" + " \\s*\n" + " 0\\d\\d \n" + " \\s*\n" + " (?(leftparen)\\)|) # right paren if and only if left paren\n" + ")? # operator code, starting with 0, optinally in parentheses\n" + "(?(?<=\\)) # if preceded by parens\n" + " \\s*| # then dash not allowed\n" + " \\s*-?\\s* # else optional dash\n" + ")\n" + "(?:\n" + " \\d | \n" + " (?<=\n" + " \\d\n" + " )\n" + " (?(sep)\n" + " (?P=sep)|\n" + " (?P<sep>[\\-\\/\\ ])\n" + " ) \n" + " (?=\n" + " \\d\n" + " )\n" + "){5,13}\n" + "\\s*# some empty spaces\n" + "$ # end\n" + "#\\d\\d\\d (?P<separator>-?) \\d\\d (?P=separator) \\d\\d $"; final String string = "SHOULD MATCH:\n" + "5344654\n" + " 5344654 \n" + "534-46-54\n" + "17189280121\n" + "+19173010176\n" + "(095)789-58-75\n" + "(095) 789-58-75\n" + "0957895875\n" + "917 229 2897\n" + "+38 (095) 5344654\n" + "53-475-34\n" + "555-1-333\n" + "1-333-484\n" + "888-333-4\n" + "(094)999-22-44\n" + "38-095-432-43-34\n" + "095-432-43-34\n" + "123456\n" + "53465\n\n" + "SHOULD NOT MATCH:\n" + "1\n" + "-1234\n" + "38-(095)-432-43-34\n" + "534-46/54\n" + "(094)999/22-44\n" + "1234--567\n" + "(345)5345654\n" + "(0955344654\n" + "095)5345654\n"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE | Pattern.COMMENTS); 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