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

/
/

Test String

Code Generator

Language

Generated Code

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`(?><(?:(?:(?:(script|style|object|embed|applet|noframes|noscript|noembed)(?:\s+(?>"[\S\s]*?"|'[\S\s]*?'|(?:(?!\/>)[^>])?)+)?\s*>)[\S\s]*?<\/\1\s*(?=>))|(?:\/?(?!body)[\w:]+\s*\/?)|(?:(?!body)[\w:]+\s+(?:"[\S\s]*?"|'[\S\s]*?'|[^>]?)+\s*\/?)|\?[\S\s]*?\?|(?:!(?:(?:DOCTYPE[\S\s]*?)|(?:\[CDATA\[[\S\s]*?\]\])|(?:--[\S\s]*?--)|(?:ATTLIST[\S\s]*?)|(?:ENTITY[\S\s]*?)|(?:ELEMENT[\S\s]*?))))>|[\S\s])*?<body(?:\s+(?>"[\S\s]*?"|'[\S\s]*?'|(?:(?!\/>)[^>])?)+)?\s*>((?:<(?:(?:(?:(script|style|object|embed|applet|noframes|noscript|noembed)(?:\s+(?>"[\S\s]*?"|'[\S\s]*?'|(?:(?!\/>)[^>])?)+)?\s*>)[\S\s]*?<\/\3\s*(?=>))|(?:\/?(?!body)[\w:]+\s*\/?)|(?:(?!body)[\w:]+\s+(?:"[\S\s]*?"|'[\S\s]*?'|[^>]?)+\s*\/?)|\?[\S\s]*?\?|(?:!(?:(?:DOCTYPE[\S\s]*?)|(?:\[CDATA\[[\S\s]*?\]\])|(?:--[\S\s]*?--)|(?:ATTLIST[\S\s]*?)|(?:ENTITY[\S\s]*?)|(?:ELEMENT[\S\s]*?))))>|[\S\s])*)<\/body\s*>`) var str = `<html> <head> <meta http-equiv="content-type" content="text/html; charset=utf-8"> </head> <!-- <body class="blah">original mock body </body> --> <body text="#000000" bgcolor="#FFFFFF"> <!CDATA[Raw unparsed character data can contain </body> with no problems!]]> <!-- Comments can also contain </body> --> So can JScript <script>/*<![CDATA[*/window.jQuery && jQuery.ready();/*]]>*/</script><script>if(window.mw){ mw.loader.state({"ext.glo</body>balCssJs.site":"ready","ext.globalCssJs.user":"ready","site":"loading","user":"ready","user.groups":"ready"}); }</script> <p>dpioaushd iuashdiu ashd</p> <p> has</p> <p>ud ashuod sh</p> <p>odu sad ha</p> <p>suod sh</p> <p>od uashod uahd<br> </p> <div class="moz-signature">-- <br> <img src="cid:part1.8C289150.C3F89C42@wssim.com.br" border="0"></div> </body> </html>` if len(re.FindStringIndex(str)) > 0 { fmt.Println(re.FindString(str),"found at index",re.FindStringIndex(str)[0]) } }

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 Golang, please visit: https://golang.org/pkg/regexp/