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)\b([a-zA-Z]*)(ne|eb|ar|(?<!nom)br|il|ay|yo|un|nio|ul|lio|go|sto|ep|mbr|ct|ubr|ov|ic|en|ero|fe(?!cha)|ma|ab|ju|jo|ja|jn|ag|se|oc|nov|dic)([a-zA-Z]*)[- \/.,\n|i]{1,3}(0[1-9]|[12][0-9]|3[01]|[1-9]|i|o[1-9zi]|i[1-9zo])[- \/.,\n|i]{1,3}[2z][0o]\d{0,2}\b`) var str = `Feb zi / zozo 10 12030 nombre fecha 01 / 2020 yl-20-2.020 FECHA: 2020-06-04 08:57:29 FECHA: 12 106 120 GARAG marzo 15/2000 mayo 15/20 jul 1/20 Junio 17/20 S: BUN Centro Médico FECHA: 05 06 - 2020 Warta carolina onerrez Nombre: 1/6/200 ONDY Soklo Fecha: nFECHA: 2020-06-04 08:57:29 FECHA: 2020-06-04 08:57:2 Bogotá, 08/jun./2020 FECHA 11/06/2020 nBOGOTAOC - 10/06/2020 1/6/200 ONDY Soklo Fecha: echa 24-unio 12020 Fecha: 17.06.2020 FECHA: 2020 24 Junio Fecha: 12 - vw FECHA VUNIO 18 18/2010 Jula 2020 FECHA: 05 06 - 2020 10 /m/ 200 2020 FECHA\nTo\nol06 \n18106 12020\n 204\nFecha: ` 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/