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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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)(?<ssn>(?<!\d{1})\d{3}[\s-]+\d{2}[\s-]+\d{4}(?!\d{1})|(?<!\d{1})\d{9}(?!\d{1}))|(?<creditCard>(?<![0-9]{1})(?:4[0-9]{12}(?:[0-9]{3})?|\d{4}[\s-]+\d{4}[\s-]+\d{4}[\s-]+\d{4}|\d{4}\d{4}\d{4}\d{4}|(?:5[1-5][0-9]{2}|222[1-9]|22[3-9][0-9]|2[3-6][0-9]{2}|27[01][0-9]|2720)[0-9]{12}|3[47][0-9]{13}|3(?:0[0-5]|[68][0-9])[0-9]{11}|6(?:011|5[0-9]{2})[0-9]{12}|(?:2131|1800|35\d{3})\d{11})(?![0-9]{1}))`) var str = `113-01-1111 213 81 1111 1553 01 1111 153 01 1111 153 01 11113 153-01-1111 153-01-1111 1313 01 11511 153-01-1111 153-01-1111 \n113-01-1111 \t113-01-11114 \t113-01-1111\t \t 113-01-1111\t \t113-01-1111 4 \t113-01-11114 \t113-01-1111 Robert Aragon 489‑36‑8350 4929‑3813‑3266‑4295 Ashley Borden 514‑14‑8905 5370‑4638‑8881‑3020 Thomas Conley 690‑05‑5315 4916‑4811‑5814‑8111` 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/