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

/
/
g

Test String

Code Generator

Language

Generated Code

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`((8|\+7?)[\- ]?)?(\(?\d{3}\)?[\- ]?)?([\d\- ]{7,10})`) var str = `======== local phone 765-43-21 7654321 765-4321 ======== operator phone (921) 765-43-21 (921) 7654321 (921) 765-4321 (921)765-43-21 (921)7654321 (921)765-4321 921765-43-21 9217654321 921765-4321 921-765-43-21 921-7654321 921-765-4321 ======== world phone +7 (921) 765-43-21 +7(921) 765-43-21 +7-(921) 765-43-21 7 (921) 765-43-21 7(921) 765-43-21 8 (921) 765-43-21 8(921) 765-43-21 8-(921) 765-43-21 8 (921) 765-43-21 8(921) 765-43-21 8-(921) 765-43-21 +7 9217654321 +79217654321 +7-9217654321 7 9217654321 79217654321 7-9217654321 8 9217654321 89217654321 8-9217654321 8 9217654321 89217654321 8-9217654321 ======== not found >>>>>>>>> 1. Коржев Артём Борисович 8-921-641-82-15; ======== bad 0 0 0 0 333 000 1 1 1205 1320 321 ======== разбор # world phone ( (8|\+?7) [\- ]? )? # operator phone ( \(? \d{3} \)? [\- ]? )? # local phone [\d\- ]{7,10}` 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/