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

/
/
img

Test String

Code Generator

Generated Code

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "^.*(po\\s*box|private\\s*bag).*$|^\\d[\\/a-zĀ-ū0-9\\s\\,\\'\\-]*$"; final String string = "Street address:\n" + "¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯\n" + "224B Clarence Street, Vogeltown, Wellington 6023\n\n" + "Rural address:\n" + "¯¯¯¯¯¯¯¯¯¯¯¯¯¯\n" + "128 Valley Road North, RD 2, Middlemarch 9597\n\n" + "PO Box:\n" + "¯¯¯¯¯¯¯\n" + "PO Box 17999, Greenlane, Auckland 1546\n\n" + "Street – with unit:\n" + "¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯\n" + "3/123 Johnstone Street West, Point Chevalier, Auckland 1022\n\n" + "Rural address with unit:\n" + "¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯\n" + "8/56 Maple Boulevard, RD 2, Wanaka 9382\n\n" + "Private Bag:\n" + "¯¯¯¯¯¯¯¯¯¯¯¯\n" + "Private Bag 93899, Auckland 0753\n\n" + "Street – with building name:\n" + "¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯\n" + "Level 2 Colombo House, 3A/1222 Colombo Street, St Albans, Christchurch 8014\n\n" + "Rural address – with building name:\n" + "¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯\n" + "Totârä Farm, 2/12543 Farm Road, RD 1, Outram 9073\n\n\n\n" + "Other addresses around the world:\n" + "¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯\n" + "813 Howard Street, Oswego, NY 13126, USA\n" + "1 Beacon Street, 33rd Floor, Boston, MA 02108, USA\n" + "Hagagatan 1 vi, SE-113 49 Stockholm, Sweden\n" + "John A. Smith, ACME Innovations Inc., PO BOX 1033, Los Angeles, CA\n" + "c/o Henry Roth, 50 Oakland Ave,#206, A City, Florida, 32104, USA\n" + "10 Downing Street, London, Greater London, SW1A 2AA, United Kingdom\n" + "Av. de Senalèche 27, 1009 Pully, Switzerland\n" + "17, Rue Bergère, 75009 Paris, France\n" + "11 Bis Av. Gabriel Péri, 38150 Roussillon, France\n" + "Apostel-Paulus-Strasse 7, 10823 Berlin, Deutschland\n"; final Pattern pattern = Pattern.compile(regex, Pattern.CASE_INSENSITIVE | 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