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 = "^(?!0{3})(?!6{3})[0-8]\\d{2}-(?!0{2})\\d{2}-(?!0{4})\\d{4}$"; final String string = "762-37-6334\n" + "429-08-8462\n" + "519-75-9429\n" + "117-08-6495\n" + "544-12-9823\n" + "841-01-5655\n" + "494-82-9724\n" + "568-11-2312\n" + "420-42-8078\n" + "396-09-7229\n" + "869-57-0924\n" + "609-44-0934\n" + "578-20-1520\n" + "835-87-3325\n" + "636-03-4578\n" + "482-19-1418\n" + "364-60-1676\n" + "780-23-8549\n" + "265-33-9416\n" + "221-88-6838\n" + "550-13-2720\n" + "336-93-2610\n" + "193-47-3307\n" + "480-82-8373\n" + "750-66-0817\n" + "122-68-3192\n" + "673-84-7164\n" + "191-03-8274\n" + "412-41-9768\n" + "888-21-9775\n" + "805-53-9154\n" + "150-26-0934\n" + "880-42-1378\n" + "853-41-1922\n" + "467-22-3453\n" + "220-91-4157\n" + "657-24-3167\n" + "229-17-5111\n" + "411-38-6337\n" + "453-61-4836\n" + "123-27-0915\n" + "105-56-0050\n" + "646-82-7847\n" + "105-17-8892\n" + "301-70-3833\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