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

r"
"
mg

Test String

Code Generator

Language

Generated Code

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`(?m)(?:^.{48}|\.)([0-9]+\.?)`) var str = `39 9 30 30 30 31 34 30 30 32 33 32 36 30 31 38 0D 0A 00014002326018.. 39 30 30 30 31 34 30 30 32 33 32 36 30 35 34 0D 900014002326054. 0A . 39 30 30 30 31 34 30 30 32 33 32 36 30 39 31 0D 900014002326091. 0A . 39 30 30 30 31 34 30 30 32 33 32 36 31 36 33 0D 900014002326163. 0A . 39 9 30 30 30 31 34 30 30 32 33 000140023 32 36 32 30 30 0D 0A 26200.. 39 9 30 30 30 31 34 30 30 32 33 32 36 32 30 30 0D 0A 00014002326200.. 39 30 30 30 31 34 30 30 32 33 32 36 31 32 32 0D 900014002326122. 0A . 39 9 30 30 30 31 34 30 30 32 33 000140023 32 36 31 35 34 0D 0A 26154.. 39 30 30 30 31 34 30 30 32 33 9000140023 32 36 31 33 31 0D 0A 26131.. 39 9 30 30 30 31 34 30 30 32 33 000140023 32 36 31 30 34 0D 0A 26104.. 39 30 30 30 31 34 30 30 32 33 32 36 30 39 30 0D 900014002326090. 0A . 39 30 30 30 31 34 30 30 32 33 32 36 31 39 37 0D 900014002326197. 0A . 39 9 30 30 30 31 34 30 30 32 33 32 36 32 30 38 0D 0A 00014002326208.. 39 30 30 30 31 34 30 30 32 33 9000140023 32 36 31 31 35 0D 0A 26115.. 39 9 30 30 30 31 34 30 30 32 33 000140023 32 36 31 36 34 0D 0A 26164.. 39 9 30 30 30 31 34 30 30 32 33 000140023 32 36 30 31 36 0D 0A 39 30 30 30 31 34 30 30 32 26016..900014002 33 3 32 36 32 34 36 0D 0A 26246.. 39 9 30 30 30 31 34 30 30 32 33 000140023 32 36 32 34 36 0D 0A 26246.. 39 9 30 30 30 31 34 30 30 32 33 000140023 32 36 30 37 39 0D 0A 26079.. 39 9 30 30 30 31 34 30 30 32 33 000140023 32 36 31 32 30 0D 0A 26120.. 39 9 30 30 30 31 34 30 30 32 33 32 36 32 32 38 0D 0A 00014002326228.. 39 30 30 30 31 34 30 30 32 33 9000140023 32 36 31 38 36 0D 0A 26186..` 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/