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

/
/
i

Test String

Code Generator

Language

Generated Code

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`(?i)(?:https?|ftp):\\?\/\\?\/sun2.[^\s\,]+`) var str = `<a aria-label="фотография" onclick="return showPhoto('-100714248_457263531', 'wall-100714248_195733', {"temp":{"x":"https:\/\/sun1.tattelecom-nbc.userapi.com\/AZsv8R78JOlrmsTJ6NR_NZpKj-RbfbWCPWQ8uA\/QnMLGnxpnYk.jpg","y":"https:\/\/sun1.tattelecom-nbc.userapi.com\/vtKcPNt6Wazn_vcPkvLAMX1MOhMz_hfRgYx28g\/cXJNEGEn2Lc.jpg","z":"https:\/\/sun2.tattelecom-nbc.userapi.com\/oZ0evVUqXklp4UGCisHHFRSaNTEfnnJO_A7lTg\/ZqD22JRrSyw.jpg","x_":["https:\/\/sun1.tattelecom-nbc.userapi.com\/AZsv8R78JOlrmsTJ6NR_NZpKj-RbfbWCPWQ8uA\/QnMLGnxpnYk",359,604],"y_":["https:\/\/sun1.tattelecom-nbc.userapi.com\/vtKcPNt6Wazn_vcPkvLAMX1MOhMz_hfRgYx28g\/cXJNEGEn2Lc",480,807],"z_":["https:\/\/sun2.tattelecom-nbc.userapi.com\/oZ0evVUqXklp4UGCisHHFRSaNTEfnnJO_A7lTg\/ZqD22JRrSyw",587,987],"base":""},"queue":1}, event)" style="width: 68px; height: 115px;background-image: url(https://sun2.tattelecom-nbc.userapi.com/aMS3yYlzjZF3H6GPY1T5oDAeIqZD5uQv4WveMw/7ToUPNMTnmo.jpg);" class="page_post_thumb_wrap image_cover page_post_thumb_last_column fl_l page_post_thumb_not_single" data-photo-id="-100714248_457263531"></a>` if len(re.FindStringIndex(str)) > 0 { fmt.Println(re.FindString(str),"found at index",re.FindStringIndex(str)[0]) } }

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/