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 = "^(?!.*@media)[\\t ]*([a-zA-Z#.:*[][^\\{\\/]*\\s*)\\{[\\s\\S]*?\\}"; final String string = "a {color: red !important;}\n" + " \n" + "#p1 {\n" + " margin-top: 20px !important\n" + " }\n\n" + "/* Client-specific styles */\n\n" + " .ExternalClass, \n" + " .ExternalClass p, \n" + " .ExternalClass span, \n" + " .ExternalClass font, \n" + " .ExternalClass td, \n" + " .ExternalClass div {\n" + " line-height: 100%;\n" + " }\n" + " \n" + " a {}\n\n" + "@media query { \n" + "a { \n" + "display:none \n" + "} \n" + "}\n\n\n" + " a\n" + " { display:none } \n" + "}\n\n" + "/* Media query for mobile viewport\n" + " #asset_container * Developer: hero graphics should be 2 x width for HD rendering.\n" + " */ \n" + " @media only screen and (max-width: 480px){\n" + " table[class=max-width-pad] {\n" + " max-width: 100% !important;\n" + " width: 100% !important;\n" + " padding-top: 15px !important;\n" + " height: auto !important;\n" + " }\n" + " #asset_container table[class=max-width]{\n" + " max-width: 100% !important;\n" + " width: 100% !important;\n" + " height: auto !important;\n" + " }\n" + " #asset_container table[class=container]{\n" + " margin: 0 auto !important;\n" + " }\n" + " #asset_container .desktop-masthead{\n" + " display: none !important;\n" + " }\n" + " #asset_container *[class].hidden. *[class=desktop-masthead]{\n" + " display: none !important;\n" + " }\n" + " #asset_container *[class].elastic{\n" + " width: 100% !important;\n" + " height: auto !important;\n" + " }\n" + " #asset_container *[class].centered{\n" + " text-align: center !important;\n" + " }\n" + " #asset_container *[class].fluid, #asset_container [class=fluid-mob]{\n" + " width: 100% !important;\n" + " }\n" + " [class=fluid-mob] {\n" + " #asset_container position: relative;\n" + " }\n" + " .mobile-show{\n" + " display: table-cell !important;\n" + " width: auto !important;\n" + " height: auto !important;\n" + " max-height: none !important;\n" + " overflow: visible !important;\n" + " visibility: visible !important;\n" + " position: relative !important;\n" + " text-align: center !important;\n" + " }\n" + " #asset_container .show-mob{\n" + " display: block !important;\n" + " max-height: none !important;\n" + " width: auto !important;\n" + " visibility: visible !important;\n" + " }\n" + " #asset_container *[class].mob-masthead{\n" + " width: 100% !important;\n" + " display: block !important;\n" + " height: auto !important;\n" + " max-height: none !important;\n" + " padding: 0 !important;\n" + " }\n" + " #asset_container *[class].mob-masthead-img{\n" + " position: absolute !important;\n" + " top: 0px !important;\n" + " display: block !important;\n" + " height: auto !important;\n" + " max-height: none !important;\n" + " padding: 0 !important;\n" + " width: auto !important;\n" + " }\n" + " [class=fluid-mob] {\n" + " display: table-cell !important;\n" + " width: auto !important;\n" + " height: auto !important;\n" + " max-height: none !important;\n" + " overflow: visible !important;\n" + " visibility: visible !important;\n" + " position: relative !important;\n" + " text-align: center !important;\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