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 = "lat"; final String string = "# Degrees minutes\n" + "# \\d+\\W+\\d+\\W+\\d+\\.?\\d*\n\n" + "\"-77.566296, 41.471044\"\n" + "5234098, 29384\n\n" + "40° 37' 03.620\\\" N\n\n" + " 39.9153 N 78.3405 W\n\n\n" + "CORNPLANTER BRIDGE QUAD.--LAT. 41-48-18.41--LONG. -78-52-51.26\n" + "LUDLOW QUAD--LAT.41-39-16.0500--LONG.-78-55-11.1200\n" + "LAT 41-45-00 LONG 75-50-00\n" + "LAT 41.73381944 LONG -75.87685278\n" + "Ref Latitude 41 81833 - Ref Longitude -75 15167\n" + "LAT 41 56' 11.28\\\" N--LON 76 52' 03.36\\\" W\n\n" + "[891] \"McNett TOWNSHIP\" \n" + "[892] \"TWP - Range - Sec\" \n" + "[893] \"MONETT TOWNSHIP,LYCOMING COUNTY,PA\n" + "LAT 41 42 12.6700\n" + "LAT 41 DEG 43-52-0300 \n" + "LAT 41.4122917\n" + "Latitude: 40.752 N\n" + "Lat. 40.72617600* N\n" + "Longitude: 80-24-41 W\n" + "Latitude: 40.653407 N\n" + "LAT: 40.687574\n" + "LAT\n" + "LAT: 40-50-13.7000\n" + "Latitude: 40.83721N\n" + "LATITUDE\n" + "Latitude 39-53-12.33 N\n" + "LATITUDE 39-53.442319 N\n" + "Latitude 39-53-43.26 N\n" + "Latitude 39.8949 N\n" + "LAT: 41-43-26.9600 N\n" + "LAT: 41-43-29.83\n" + "LAT: 41*51'42.99\\\" N\n" + "LAT: 41-46-9.8700 N\n" + "LATITUDE: 41* 42' 40.19\\\"\n\n" + "41-42-40.19 LAT\n\n" + "API # 37-015-208801-00--X=2201217.34E Y=632183.50N--LAT\"\n" + "03-029-01"; 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