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

/
/
gmi

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 = "^hsla?\\(\\s*(?<h>[-+]?\\d{1,3}(?:\\.\\d+)?)(deg|grad|rad|turn)?\\s*(?:,\\s*|\\s+)\\s*(?<s>[-+]?\\d{1,3}(?:\\.\\d+)?)%\\s*(?:,\\s*|\\s+)\\s*(?<l>[-+]?\\d{1,3}(?:\\.\\d+)?)%\\s*(?:,\\s*|\\s+)?(?:\\s*\\/?\\s*(?<alpha>[-+]?[\\d.]+%?)\\s*)?\\)$"; final String string = "\n" + "hsl(.9, .99%, .999%, .9999)\n" + "hsl(0240, 0100%, 0050%, 01) \n" + "hsl(2400, 1000%, 1000%, 10)\n" + "hsl(-2400.01deg, -1000.5%, -1000.05%, -100)\n" + "hsl(2.40e+2, 1.00e+2%, 5.00e+1%, 1E-3)\n\n" + "hsl(-240, -100%, -50%, -0.1)\n" + "hsl(+240, +100%, +50%, +0.1)\n" + "HSL(240Deg, 100%, 50%)\n" + "hsl(240, 100%, 50%, 10%)\n" + "hsl(150deg 30% 60%)\n" + "hsl(0.3turn 60% 45% .7)\n" + "hsl(0.3grad 60% 45% / .7)\n" + "hsl(0.3rad 60% 45% / .7)\n" + "hsl(12 60% 45% / .7)\n" + "hsl(120, 100%, 50%)\n" + "hsl(0, 0%, 0%)\n" + "hsl(60, 50%, 75%)\n" + "hsl(270, 80%, 60%)\n" + "hsl(200, 20%, 40%)\n" + "hsl(340, 90%, 80%)\n" + "hsla(120, 100%, 50%, 0.5)\n" + "hsla(0, 0%, 0%, 0.2)\n" + "hsla(60, 50%, 75%, 0.8)\n" + "hsla(270, 80%, 60%, 0.4)\n" + "hsla(200, 20%, 40%, 0.6)\n" + "hsla(340, 90%, 80%, 0.1)\n" + "hsl(120 100% 50%)\n" + "hsl(0 0% 0%)\n" + "hsl(60 50% 75%)\n" + "hsl(270 80% 60%)\n" + "hsl(200 20% 40%)\n" + "hsl(340 90% 80%)\n" + "hsla(120 100% 50% / 0.5)\n" + "hsla(0 0% 0% / 0.2)\n" + "hsla(60 50% 75% / 0.8)\n" + "hsla(270 80% 60% / 0.4)\n" + "hsla(200 20% 40% / 0.6)\n" + "hsla(340 90% 80% / 0.1)\n" + "hsl(240, 100%, 50%)\n" + "hsl(240, 100%, 50%, 0.1)\n\n" + "hsl(240,100%,50%,0.1)\n" + "hsl(180deg, 100%, 50%, 0.1)\n" + "hsl(3.14rad, 100%, 50%, 0.1)\n" + "hsl(200grad, 100%, 50%, 0.1)\n" + "hsl(0.5turn, 100%, 50%, 0.1)\n\n" + "hsl(240.5, 99.99%, 49.999%, 0.9999)\n\n\n" + "hsl(240.0, 100.00%, 50.000%, 1.0000)\n\n" + "hsl(240 100% 50%)\n" + "hsl(240 100% 50% / 0.1)\n" + "hsla(240, 100%, 50%)\n" + "hsla(240, 100%, 50%, 0.1)\n"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE | Pattern.CASE_INSENSITIVE); 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