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

/
/
gmi

Test String

Substitution

Processing...

Code Generator

Language

Generated Code

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`(?mi)^.*(([\w\d]{5}-?){3}).*$`) var str = `12 DIG ARTIFEX Bundle 3 9 Clues 2: The Ward STEAM 5MQ7W-N7PAT-V0QQL YES Mark as used 13 DIG ARTIFEX Bundle 3 9 Clues: The Secret of Serpent Creek STEAM PEMFX-48T80-20ANW YES Mark as used 14 DIG Super Bundle 76 HellAngel STEAM FENFR-LQ0N3-TNLR0 YES Mark as used 1 DIG Points Purchase Monsti STEAM BCI7T-Z9P4Q-LGJ9T YES Mark as used 2 DIG Super Bundle 74 Wooden Floor 2 - Resurrection STEAM LPL6L-2LJ74-GWG3W YES 3 DIG Super Bundle 74 Warriors of Vilvatikta STEAM 90LPI-T5KC2-C4W6M YES 4 DIG Super Bundle 74 Final Quest STEAM IJRID-JYGH3-3M5C7 YES 5 DIG Super Bundle 74 Gold Rush! - Anniversary STEAM 6D7DA-8EZZP-DET6A YES 6 DIG Super Bundle 75 Sleeping Valley STEAM 8AFHR-C0X43-DAG74 YES ` var substitution = "$1" fmt.Println(re.ReplaceAllString(str, substitution)) }

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/