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

/
/
mg

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 = "^(([NnSs+-])?([0-8]?\\d(\\.\\d*)?|90(\\.0*)?)([°˚º^~*NnSs+-])*)([,:;\\s|\\/\\\\-]+)(([EeWw+-])*([0]?\\d?\\d(\\.\\d*)?|1[0-7]\\d(\\.\\d*)?|180(\\.0*)?)[°˚º^~*]*([EeWw+-])*)[\\s]*$"; final String string = "//check all zeros\n" + "0 0\n" + "0.0 0.0\n" + "0.000 0.000\n" + "0.0000 0.0000\n\n" + "//check plus and minus signs\n" + "+0 0\n" + "+0.0 0.0\n" + "+0.000 0.000\n" + "+0.0000 0.0000\n\n" + "0 +0\n" + "0.0 +0.0\n" + "0.000 +0.000\n" + "0.0000 +0.0000\n\n" + "+0 +0\n" + "+0.0 +0.0\n" + "+0.000 +0.000\n" + "+0.0000 +0.0000\n\n" + "-0 0\n" + "-0.0 0.0\n" + "-0.000 0.000\n" + "-0.0000 0.0000\n\n" + "0 -0\n" + "0.0 -0.0\n" + "0.000 -0.000\n" + "0.0000 -0.0000\n\n" + "-0 -0\n" + "-0.0 -0.0\n" + "-0.000 -0.000\n" + "-0.0000 -0.0000\n\n" + "0+ 0\n" + "0.0+ 0.0\n" + "0.000+ 0.000\n" + "0.0000+ 0.0000\n\n" + "0 0+\n" + "0.0 0.0+\n" + "0.000 0.000+\n" + "0.0000 0.0000+\n\n" + "0- 0\n" + "0.0- 0.0\n" + "0.000- 0.000\n" + "0.0000- 0.0000\n\n" + "0 0-\n" + "0.0 0.0-\n" + "0.000 0.000-\n" + "0.0000 0.0000-\n\n" + "0+ 0+\n" + "0.0+ 0.0+\n" + "0.000+ 0.000+\n" + "0.0000+ 0.0000+\n\n" + "0- 0-\n" + "0.0- 0.0-\n" + "0.000- 0.000-\n" + "0.0000- 0.0000-\n\n" + "//check hemipshere\n" + "0N 0\n" + "0.0N 0.0\n" + "0.000N 0.00\n" + "0.0000N 0.000\n\n" + "0N 0E\n" + "0.0N 0.0E\n" + "0.000N 0.00E\n" + "0.0000N 0.000E\n\n" + "0N 0W\n" + "0.0N 0.0W\n" + "0.000N 0.00W\n" + "0.0000N 0.000W\n\n" + "0S 0\n" + "0.0S 0\n" + "0.000S 0\n" + "0.0000S 0\n\n" + "0S 0E\n" + "0.0S 0.0E\n" + "0.000S 0.00E\n" + "0.0000S 0.000E\n\n" + "0S 0W\n" + "0.0S 0.0W\n" + "0.000S 0.00W\n" + "0.0000S 0.000W\n\n" + "//check degree symbols\n" + "0° 0°\n" + "0.0° 0.0°\n" + "0.000° 0.000°\n" + "0.0000° 0.0000°\n\n" + "0˚ 0˚\n" + "0.0˚ 0.0˚\n" + "0.000˚ 0.000˚\n" + "0.0000˚ 0.0000˚\n\n" + "0º 0º\n" + "0.0º 0.0º\n" + "0.000º 0.000º\n" + "0.0000º 0.0000º\n\n" + "0^ 0^\n" + "0.0^ 0.0^\n" + "0.000^ 0.000^\n" + "0.0000^ 0.0000^\n\n" + "0* 0*\n" + "0.0* 0.0*\n" + "0.000* 0.000*\n" + "0.0000* 0.0000*\n\n" + "0~ 0~\n" + "0.0~ 0.0~\n" + "0.000~ 0.000~\n" + "0.0000~ 0.0000~\n\n" + "//check sperators\n\n" + "0,0\n" + "0.0,0.0\n" + "0.000,0.000\n" + "0.0000,0.0000\n\n" + "0-0\n" + "0.0-0.0\n" + "0.000-0.000\n" + "0.0000-0.0000\n\n" + "0:0\n" + "0.0:0.0\n" + "0.000:0.000\n" + "0.0000:0.0000\n\n" + "0;0\n" + "0.0;0.0\n" + "0.000;0.000\n" + "0.0000;0.0000\n\n" + "0|0\n" + "0.0|0.0\n" + "0.000|0.000\n" + "0.0000|0.0000\n\n" + "0/0\n" + "0.0/0.0\n" + "0.000/0.000\n" + "0.0000/0.0000\n\n" + "0\\0\n" + "0.0\\0.0\n" + "0.000\\0.000\n" + "0.0000\\0.0000\n\n" + "90,180\n" + "45,45\n\n\n" + "//invalid\n" + "90.123 0.0\n" + "91.0 0\n" + "91.00 0\n" + "91.0 0.0\n" + "91.00 0.00\n" + "0 180.1\n" + "0 181\n\n\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