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

/
/
gui

Test String

Code Generator

Language

Generated Code

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`(?i)(http:\/\/\s*|https:\/\/\s*|ftp:\/\/\s*)?(www\s*)?(?(1)([.]\s*))?(?(2)([.]\s*))?([a-zA-Z0-9.-]{2,256})(\s*[.]\s*)(ru|pl|kz|by|ua|com|in|pt|br|co.uk)(?![a-zA-Z])([?|#]{1}[=&#a-zA-Z0-9]{2,128})?`) var str = `http:// www . alga-deweloper . pl TIRA UM: Ńąm iuvaret tus electram. Tempor http://www.google.com in eam, ut dictas disputando vim. NO TIRA: kuchnia.Na impedit ne, cu pri vęri nostro, mel ut integre praesent dissentias. TIRA UM: Ceteros inćorruptę google.com?sad=asd id, saępe ńullam vix ut. TIRA UM: Eam ut ępićurei adólesćens. Nam ąd sumo agąm. Vis te dicam https://www.google.com. TIRA UM: Has ęa, ei cóngue tęmpóribus comprehęnsam http://asdasd asdas da www.amazon.co.uk. NÃ TIRA: No nónumy doćtus sd.asd.comia uma pizza.nan asjJ.domain djJ.co asd.uk, altęra cónśetetur ut. SECRETO: Hinc expetenda ocurreret at has. Ex eum ętiam http:// asdasdasd . com Cu vix. SECRETO: Hinc expetenda ocurreret at has. Ex eum ętiam www . asdasdasd . com Cu vix. SECRETO: http:// www . alga-deweloper . pl sdsdfsdfsdf NÃ TIRA: Altęra cónśetetur ut ?asd=asdd asdasd sdfsdfsdfsdf. TIRA UM: Ceteros inćorruptę http://www.google6.com#sdfsdf id, saępe ńullam vix ut. TIRA UM: Ceteros inćorruptę http://www.google6.com?asdads=asd&asasd=sdasd#sdfsdf id, ńullam vix ut. TIRA UM: Altęra cónśetetur www.donet.come sdffd. domain . com asdasd TIRA UM: Altęra cónśetetur www.donet.come sdffd. www . aasd . com asdasd TIRA UM: http:// www . alga-deweloper . pl` for i, match := range re.FindAllString(str, -1) { fmt.Println(match, "found at index", 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 Golang, please visit: https://golang.org/pkg/regexp/