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 = "^([\\s]{2,})(?!.*[&@])(.*?)([,\\{])\\n"; final String string = "#term-header {\n" + " padding: 20px 0 17px;\n" + " margin: 0 10px 30px;\n" + " &::before,\n" + " &::after {\n" + " margin-left: -11px;\n" + " border-width: 12px 10.5px 0 10.5px;\n" + " }\n" + " &::before {\n" + " bottom: -12px;\n" + " }\n" + " &::after {\n" + " bottom: -10px;\n" + " }\n" + " h1 {\n" + " font-size: 20px;\n" + " span {\n" + " font-size: 27px;\n" + " }\n" + " }\n" + " dl {\n" + " margin: 20px 0 0;\n" + " dt {\n" + " width: 100px;\n" + " }\n" + " dd {\n" + " font-size: 11px;\n" + " }\n" + " }\n" + "}\n\n" + ".slick-next,\n" + ".slick-prev {\n" + " width: 35px;\n" + " height: 35px;\n" + "}\n" + ".slick-prev {\n" + " left: 5px;\n" + " transform: translate3d(-30px, 0, 0);\n" + " &::after {\n" + " left: 14px;\n" + " }\n" + "}\n" + ".slick-next {\n" + " right: 5px;\n" + " transform: translate3d(30px, 0, 0);\n" + " &::after {\n" + " right: 14px;\n" + " }\n" + "}\n" + ".ready.inview {\n" + " .slick-prev {\n" + " &.slick-disabled {\n" + " transform: translate3d(-30px, 0, 0);\n" + " }\n" + " }\n" + " .slick-next {\n" + " &.slick-disabled {\n" + " transform: translate3d(30px, 0, 0);\n" + " }\n" + " }\n" + "}\n\n" + ".wp-editor {\n" + " font-family: var(--fontFamily);\n" + " font-size: var(--fontSize);\n" + " line-height: var(--lineHeight);\n" + " & h3,\n" + " & h4,\n" + " & p {\n" + " margin: var(--wpEditorMargin) 0;\n" + " overflow: hidden;\n" + " &:first-child {\n" + " margin-top: 0;\n" + " }\n" + " &:last-child {\n" + " margin-bottom: 0;\n" + " }\n" + " }\n" + " & h3 {\n" + " font-size: 14px;\n" + " }\n" + " & h4 {\n" + " font-size: 13px;\n" + " }\n" + " & a {\n" + " color: var(--linkColor);\n" + " text-decoration: underline;\n" + " &:hover {\n" + " text-decoration: none;\n" + " }\n" + " }\n" + " & img {\n" + " max-width: 100%;\n" + " height: auto;\n" + " }\n" + " & blockquote {\n" + " padding-left: 15px;\n" + " margin: var(--wpEditorMargin) 0;\n" + " font-weight: bold;\n" + " border-left: 5px solid var(--borderColor);\n" + " @media (--viewport-medium) {\n" + " padding-left: 35px;\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