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

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`(?m)^(?=.{6,284}$)[^\W_](?:[+\w.-]*[^\W_])?@[^\W_](?:\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.|(?:[\w-]+\.)+)(?:[a-zA-Z]{2,13}|[0-9]{1,3})\]?$`) var str = `.abc@ornekeposta.com _abc@ornekeposta.com 9abc.@ornekeposta.com !@ornekeposta.com a!@ornekeposta.com ö@ö@.ö #4+^%+@göl.çöz !'^+%&&/)=?:_@^+%+^&%(.+%^+%%+/&%&.com a_@a.aa 21322534@435345345.4353.4543 a@aa.aa 1@12.co a.1@555555.com a@ornekeposta.com 9abc@ornekeposta.com abc@ornekeposta.org.tr m@it.ai.tr.cz.ru.dart name@surname.aero AAAA@AAA.AA deneme+tag@deneme.com very-important@person.international istanbul-istanbul-istanbul-istanbul-istanbul-istanbul-istanbul-istanbul-istanbul-istanbul-istanbul-istanbul-istanbul-istanbul-istanbul-istanbul-istanbul-istanbul-istanbul.istanbul.istanbul.istanbul+istanbul@4istanbul.istanbul-istanbul-istanbul-istanbul-istanbul.istanbul.ista.istanbul ` 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/