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)<div\sid=\"olpProductDetails[\s\S]*?<h1[\s\S]*?<div[\s\S]*?<span[\s\S]*?>[\s\S]*?\s*<\/span>\s*<\/div>\s*([\s\S]*?)[\s]+<\/h1>`) var str = `<div id="olpProductDetails" class="a-fixed-left-grid-col a-col-right" style="padding-left:0%;float:left;"> <h1 class="a-size-large a-spacing-none" role="main"> <div class="a-section a-spacing-none olpSubHeadingSection"> <span class="a-size-base a-color-secondary"> </span> </div> Keds Women's Chillax Washed Laceless Slip-On Sneaker, Taupe, 8 M US </h1> <div id="olpProductByline" class="a-section a-spacing-mini"> by Keds </div> <div class="a-section a-spacing-small"> ` 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/