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 single character of: a, b, c or d
    [[ab][cd]]
  • 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]
  • Character class intersection
    [\w&&[^\d]]
  • 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

"
"
mgisd

Test String

Code Generator

Language

Generated Code

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`(?mis)/^(4\d{3}\s?\d{4}\s?\d{4}\s?\d{0,4}|5[1-5]\d{2}\s?\d{4}\s?\d{4}\s?\d{0,4}|2[2-7]\d{2}\s?\d{4}\s?\d{4}\s?\d{0,4}|6[45]\d{2}\s?\d{4}\s?\d{4}\s?\d{0,4}|3[47]\d{2}\s?\d{6}\s?\d{5}|(62[4-6]|628[2-8]|6011|65061[1-9]|65060[1-9]|65[2-9]\d{2}|64[4-9]|622(1(2[6-9]|[3-9]\d)|[2-8]\d{2}|9([01]\d|2[0-5])))\s?\d{4}\s?\d{4}\s?\d{0,4}|(?:2131|1800|35\d{2})\s?\d{4}\s?\d{4}\s?\d{4}|3(?:0[0-5]|[689]\d)\s?\d{6}\s?\d{4})$/`) var str = `376680816376961` 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/