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

Substitution

Processing...

Code Generator

Language

Generated Code

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`(?m)^([^\x00-\x20\x22\x28\x29\x2c\x2e\x3a-\x3c\x3e\x40\x5b-\x5d\x7f-\xff]+|\x22([^\x0d\x22\x5c\x80-\xff]|\x5c[\x00-\x7f])*\x22)(\x2e([^\x00-\x20\x22\x28\x29\x2c\x2e\x3a-\x3c\x3e\x40\x5b-\x5d\x7f-\xff]+|\x22([^\x0d\x22\x5c\x80-\xff]|\x5c[\x00-\x7f])*\x22))*\x40([^\x00-\x20\x22\x28\x29\x2c\x2e\x3a-\x3c\x3e\x40\x5b-\x5d\x7f-\xff]+|\x5b([^\x0d\x5b-\x5d\x80-\xff]|\x5c[\x00-\x7f])*\x5d)(\x2e([^\x00-\x20\x22\x28\x29\x2c\x2e\x3a-\x3c\x3e\x40\x5b-\x5d\x7f-\xff]+|\x5b([^\x0d\x5b-\x5d\x80-\xff]|\x5c[\x00-\x7f])*\x5d))*$`) var str = `criscrisaaaa@gmail.com.es mminighin@alpenite.com !mminighin@alpenite.com #mminighin@alpenite.com $mminighin@alpenite.com %mminighin@alpenite.com &mminighin@alpenite.com 'mminighin@alpenite.com *mminighin@alpenite.com +mminighin@alpenite.com -mminighin@alpenite.com /mminighin@alpenite.com =mminighin@alpenite.com ?mminighin@alpenite.com ^mminighin@alpenite.com _mminighin@alpenite.com \`mminighin@alpenite.com {mminighin@alpenite.com |mminighin@alpenite.com }mminighin@alpenite.com ~mminighin@alpenite.com 0mminighin@alpenite.com 1mminighin@alpenite.com 2mminighin@alpenite.com 3mminighin@alpenite.com 4mminighin@alpenite.com 5mminighin@alpenite.com 6mminighin@alpenite.com 7mminighin@alpenite.com 8mminighin@alpenite.com 9mminighin@alpenite.com 10mminighin@alpenite.com prettyandsimple@example.com very.common@example.com disposable.style.email.with+symbol@example.com other.email-with-dash@example.com fully-qualified-domain@example.com user.name+tag+sorting@example.com x@example.com "very.(),:;<>[]\".VERY.\"very@\\ \"very\".unusual"@strange.example.com example-indeed@strange-example.com admin@mailserver1 #!$%&'*+-/=?^_\`{}|~@example.org "()<>[]:,;@\\\"!#$%&'-/=?^_\`{}| ~.a"@example.org example@s.solutions user@localserver user@[2001:DB8::1] .user@[2001:DB8::1]` var substitution = "" fmt.Println(re.ReplaceAllString(str, substitution)) }

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/