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)\(\\x07([0-9]{4,})|\(\\t([0-9]{4,})\(`) var str = `#걸려야함 4nYoywMzx6630636\x010\x0200\x011\x011\x03\x14\x03\x14\x03\x03\x0820210430\x0820410430\x0820210430\x0820410430\x03(\x071000000(\x041190\x03.\x0202(\x010\x03d\x08207504306AAAU(\x0230\x1e012020460104600200000000020020\x1e01202046010460020000000002002030630636009910200201020020000999--020020------2-01--\x03CTL\x013(\x010(\x010(\x010(\x010(\x010(\x010(\x010\x03#NA(\x011(\x010(\x010(\x010\x011\x03(\x011\x03-\x01 \x03#NA\x011\x01 \x011\x0200(\x041190(\x010\x03N갱신형 재진단암진단비(2년 대기형)[기본계약](계속보장형)\x03\x01 \x012\x03#NA\x03\x03#NA(\x041190\x03#NA(\x010\x012\x03#NA\x03#NA\x010(\x010(\x010(\x010(\x010(\x010(\x010\x03(\x010\x03\x03\x03\x03(\x010\x0220\x01 \x01 (\x010\x03\x01{\x03\x03\x03\n 4nYpMQSq0v620255\x010\x0200\x011\x011\x03\x01\x03\x01\x03\x03\x0820210430\x0820220430\x0820210430\x0820220430\x03(\x0850000000(\x041320\x03*\x0201(\x0215\x03\x08203604306AABI(\x011\x1c0100104223310010000000001001\x1c0100104223310010000000001001/0620255009990009999000999000999----------2-01--\x03CTL\x013(\x010\x011(\x010(\x010(\x010(\x010(\x010(\x010\x03#NA(\x011(\x010(\x010(\x010\x011\x03(\x011\x03)\x01 \x03#NA\x011\x01 \x011\x0200(\x041811(\x010\x03\x1f갱신형 상해입원의료비\x03\x03100\x011\x03#NA\x03\x03#NA(\x041320\x013(\x010\x012\x03#NA\x03#NA\x011(\x010(\x010(\x010(\x010(\x010(\x010\x03(\x010\x03\x03\x03\x03(\x010\x0201\x01 \x01 (\x010\x03_\x01{\x03\x03\x02\n \(\\x08([0-9]{4,})\([0-9]{3,} '4nXfg3E6Qb(\x011(\x011\x03CTL\x133190026942021031120\x0201\x040001\n' ` 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/