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)(?P<idval>\b[A-F\d]{40}\b)(.|\n)*?(?P<ip>\b((25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\b).?(?P<date>\b\d{4}(-\d{2}){2} (\d{2}:){2}\d{2}\b)`) var str = ` IDVal 4273E6D162ED2717A1CF4207A254004CD3F5307B Posted 2022-12-28 07:35:55 Status 2022-12-28 08:10:11 Entry 21.12.26.23 2022-12-28 13:10:30 Entry 113.132.26.203 2022-12-28 12:56:30 Entry 31.12.27.22 2022-12-28 12:35:30 IDVal 0D12D8E72DED99EE31BB0C57789352BED0CEEEFF Posted 2022-12-28 07:30:55 Status 2022-12-28 06:10:11 Entry 51.102.52.36 2022-12-28 07:10:30 IDVal D947623B30C9D6E142E7D90FC7368B1A2A4F5045 Posted 2010-12-27 04:35:55 Status 2010-12-26 03:10:11 Entry 11.12.147.2 2022-12-28 07:20:30 Entry 91.177.62.236 2022-12-27 07:10:30 Entry 78.102.152.89 2022-12-25 07:10:30` 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/