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 = "\\b[a-zA-Z1-9]((([]!#$%^&*()])(?!\\g<-1>))|[a-zA-Z1-9]){0,63}((?<![]!#$%^&*()])@)(\\w+\\.)+(com|net|gov|mil|org|edu)\\b"; final String string = "(850)867-5309\n" + "850-867-5309 \n" + "(850_867_5309)\n" + "850.867.5309\n" + "[Hello]\n" + "C:\\windows\\system32\n" + "!MrColdsnow@jimbob.steve.com\n" + "BaconTaters@osu.edu\n" + "1.2.3.4\n" + "11.22.33.44\n" + "111.222.111.222\n" + "192.168.0.5\n" + "1234.1234.1234.1234\n" + "956.458.875.259\n" + "...\n" + "123-45-6789\n" + "ABB\n" + "ABAB\n" + "The quick brown dog jumped over the lazy programmer.\n" + "There are fifty states in the United States.\n" + "Breathe because RegEx is easy.\n" + "42 ( Answer to the Ultimate Question of Life, the Universe, and Everything )\n" + "73 (the best number) ( 7 is the 4th prime number and 3 is the 2nd prime number (42) )\n" + " (not to mention, 73 is the 21st prime number and 37 is the 12th (both numbers mirrored) and\n" + " 73 in binary is 1001001 (a palindrome) )\n" + "bat cat hat rat brat chat\n" + "eat fat gat lat mat oat pat sat vat \n" + "my dog likes a good hotdog\n" + "dogs like hotdogs but not our \"person\" dogma\n" + "dog\n" + "2dog\n" + "snoop2dog\n" + "10\n" + "150\n" + "345\n" + "14\n" + "0789\n" + "7980\n" + "ICMP echo request\n" + "ICMP echo reply\n" + "deed peep noon Otto Abba\n" + "level kayak madam radar refer civic\n" + "redder revver\n" + "racecar rotator deified repaper reviver\n" + "List of trucks that are better than the F150:\n" + "1. GMC Sierra\n" + "2. Chevy Silverado\n" + "3. Toyota Tundra\n" + "4. Nissan Titan\n" + "5. Toyota Tacoma\n" + "6. GMC Canyon\n" + "7. Nissan Frontier\n" + "8. Jeep Gladiator\n" + "9. Honda Ridgeline\n" + "10. Chevy Cavalier\n" + "moose mouse mooooose m3se\n" + "Mississippi"; 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