Regular Expressions 101

Save & Share

  • Regex Version: ver. 1
  • Update Regex
    ctrl+⇧+s
  • Save new Regex
    ctrl+s
  • Add to Community Library

Flavor

  • PCRE2 (PHP >=7.3)
  • PCRE (PHP <7.3)
  • ECMAScript (JavaScript)
  • Python
  • Golang
  • Java 8
  • .NET 7.0 (C#)
  • Rust
  • Regex Flavor Guide

Function

  • Match
  • Substitution
  • List
  • Unit Tests

Tools

Sponsors
There are currently no sponsors. Become a sponsor today!
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)var\s(\w+)\s?\=\s?(\d+|\"[^\n"]*\"|\'[^\n']*\')\s?\;`) var str = `<html> <head>~~</head> <body> <div>contents</div> <script> var value1 = 55;var value2= 27; var value3 = 'T';var value4 = "FIT#$%SIZE"; var value5 = '{\"P00000WJ000E\":{\"stock_price\":\"0.00\",\"use_stock\":true,\"use_soldout\":\"T\",\"is_display\":\"T\",\"is_selling\":\"T\",\"option_price\":79000,\"option_name\":\"FIT#$%SIZE\",\"option_value\":\"NOBLE-44\",\"stock_number\":26,\"option_value_orginal\":[\"NOBLE\",\"44\"],\"use_stock_original\":\"T\",\"use_soldout_original\":\"T\",\"use_soldout_today_delivery\":\"F\",\"is_auto_soldout\":\"F\",\"is_mandatory\":\"T\",\"option_id\":\"000E\",\"is_reserve_stat\":\"N\",\"item_image_file\":null,\"origin_option_added_price\":\"0.00\"}}';var value6 = '1';var value7 = 'string;must-catch'; var value8 = 8; var value9 = 'S'; var value10 = 'T'; </script> </body> </html>` 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/