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(`(\d[ \-.)]{0,3}){11,20}|(\b[\d]{3}\b)[^,.]`) var str = `1546 4 8 6 2 6 4 1 1 5 3 6 6 6 7 7 1 5378 2052 1163 1153 6011-7614 4775 1364 333 112,55 mdsksajfk 05536080 214 12/05 12/08 122sss 222222222222111 22464 222 222ss, 222,22 22.22 333215122 22 33 123456789012 122.44 445 1546 4 8 6 2 6 4 1 1 5 3 6 6 6 7 7 1 5378 2052 1163 1153 6011-7614 4775 1364 333 112,55 mdsksajfk 11947285580 (11)947285580 1194728-5580 11 94728 5580 346.549.668-32 46254966832 31604523875 10154511,55 12/56/12019` 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/