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

/
/
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 = "^(?:N\\d|N\\d{2}|(?:EX|N|P|V8|XU)\\d{3}|(?:B|CP|CU-T|HL|JA|JU|N|OB|OE|OK|RPC|V7|VN|YV)\\d{4}|(?:4K|4L|B|EK|ER|EW|EX|EY|N|RA|RDPL|UK|UN|UR)\\d{5}|RA\\d{4}K|VN[A-Z]\\d{3}|4K[A-Z]{2}\\d{2}|(?:4L|UR)[A-Z]{3}|XC[A-Z]{3}\\d{2}|(?:HJ|HK|N)\\d{4}[A-Z]|HP\\d{4}[A-Z]{3}|(?:JA|N|YV)\\d{3}[A-Z]|(?:EW|HI|N)\\d{3}[A-Z]{2}|N\\d{2}[A-Z]|(?:JA|N)\\d{2}[A-Z]{2}|N\\d[A-Z]|N\\d[A-Z]{2}|(?:EZ|JA|OK)[A-Z]\\d{3}|(?:9XR|A4O|A9C|B-H|B-K|B-L|B-M|F-OD|F-OG|F-OH|OY-B|OY-H|OY-X|VP-A|VP-B|VP-C|VP-F|VP-G|VP-L|VP-M|VQ-H|VQ-T)[A-Z]{2}|(?:4K|HZ|V8|YJ)[A-Z]{2}\\d|(?:HZ|YJ)[A-Z]{2}\\d{2}|(?:3A|3B|3C|3D|3X|4O|4R|4U|4X|5A|5B|5H|5N|5R|5T|5U|5V|5W|5X|5Y|6O|6V|6W|6Y|7O|7P|7Q|7T|8P|8Q|8R|9A|9G|9H|9J|9K|9L|9M|9N|9Q|9U|9V|9Y|A2|A3|A5|A6|A7|A8|A9C|AP|C2|C3|C5|C6|C9|CC|CF-|C-F|C-G|C-I|CN|CR|CS|CX|D2|D4|D6|DQ|E3|E5|EC|EI|EP|ER|ES|ET|F-O|H4|HA|HB|HC|HH|HR|HS|HZ|J2|J3|J5|J6|J7|J8|JY|LN|LQ|LV|LX|LY|LZ|OD|OE|OH|OK|OM|OO|OY|OY|OY|P2|P4|PH|PJ|PK|PP|PR|PT|PU|PZ|S2|S5|S7|S9|SE|SP|ST|SU|SX|T2|T3|T7|T9|TC|TF|TG|TI|TJ|TL|TN|TR|TS|TT|TU|TY|TZ|V2|V3|V4|V5|V6|V8|VH|VT|XA|XB|XC|XT|XY|XZ|YA|YI|YK|YL|YN|YR|YS|YU|Z|Z3|ZA|ZK|ZL|ZM|ZP|ZS|ZT|ZU)[A-Z]{3}|HZ[A-Z]{3}\\d|OK[A-Z]\\d{2}|(?:D|F|G|I|M)[A-Z]{4}|YV(?:KW\\d|O\\d{3}|SATA\\d))$"; final String string = "N5441V"; 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