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

/
/
gi

Test String

Code Generator

Language

Generated Code

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`(?i)([+-]? ?[0-9]{1,3}(deg|°|\*)) ?([0-9]{1,2}\.?[0-9]*?(min|'|’| ))? ?([0-9]{1,2}\.?[0-9]*?(sec|"|”| ))?( ?[NSEW]?)`) var str = `This is the start of a validator for Degrees Minutes Seconds for GeoMapping 38° 24' 55" -78deg 28' 52" W 12345 North south aasdf#asdf 125415 S asdf/asdf/asdf asdf"ASDF""asdf' !@#$%^&*()_+.[]__ ASDF __ASDF__ 38° 24' -78deg 28' 52" W 38° 24' 55", -78deg 28' 52" W -39.1234567 77.123456 77.123456 38.0818651958795, -78.4788168125323 38 -78 38N -78 38 N -78 38 N, -78 ` 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/