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)(<)(.*?[^>]+)`) var str = `<table class=\"mce-item-table\" style=\"border-collapse: collapse; width: 676px; word-break: break-all; outline: none; height: 5px; border-bottom: 1px solid rgb(27, 105, 178); text-align: left;\" contenteditable=\"false\"><caption style=\"display: none; \" data-mce-style=\"display: none; outline: grey solid 2px;\"></caption><tbody><tr><th style=\"outline: none; width: 95px; text-align: left; vertical-align: top; background-color: rgb(27, 105, 178);\" data-mce-style=\"outline: none; width: 95px; text-align: left; vertical-align: top; background-color: #1b69b2;\"><span style=\"color: rgb(255, 255, 255);\" data-mce-style=\"color: #ffffff;\"><strong>Application</strong></span></th><th style=\"outline: none; width: 173px; text-align: left; vertical-align: top; background-color: rgb(27, 105, 178);\" data-mce-style=\"outline: none; width: 173px; text-align: left; vertical-align: top; background-color: #1b69b2;\"><span style=\"color: rgb(255, 255, 255);\" data-mce-style=\"color: #ffffff;\"><strong>Platform</strong></span></th><th style=\"outline: none; width: 212px; text-align: left; vertical-align: top; background-color: rgb(27, 105, 178);\" data-mce-style=\"outline: none; width: 212px; text-align: left; vertical-align: top; background-color: #1b69b2;\"><span style=\"color: rgb(255, 255, 255);\" data-mce-style=\"color: #ffffff;\"><strong>URL</strong></span></th><th style=\"outline: none; width: 194px; text-align: left; vertical-align: top; background-color: rgb(27, 105, 178);\" data-mce-style=\"outline: none; width: 194px; text-align: left; vertical-align: top; background-color: #1b69b2;\"><span style=\"color: rgb(255, 255, 255);\" data-mce-style=\"color: #ffffff;\"><strong>Cost</strong></span></th></tr><tr><td style=\"outline: none; width: 95px; text-align: left; vertical-align: top; background-color: rgb(255, 253, 233);\" data-mce-style=\"outline: none; width: 95px; text-align: left; vertical-align: top; background-color: #fffde9;\">FileZilla</td><td style=\"outline: none; width: 173px; text-align: left; vertical-align: top; background-color: rgb(255, 253, 233);\" data-mce-style=\"outline: none; width: 173px; text-align: left; vertical-align: top; background-color: #fffde9;\">Windows, Mac, Linux</td><td style=\"outline: none; width: 212px; text-align: left; vertical-align: top; background-color: rgb(255, 253, 233);\" data-mce-style=\"outline: none; width: 212px; text-align: left; vertical-align: top; background-color: #fffde9;\"><a>https:/<wbr>/<wbr>filezilla-project.org</a></td><td style=\"outline: none; width: 194px; text-align: left; vertical-align: top; background-color: rgb(255, 253, 233);\" data-mce-style=\"outline: none; width: 194px; text-align: left; vertical-align: top; background-color: #fffde9;\">Free download</td></tr><tr><td style=\"outline: none; width: 95px; text-align: left; vertical-align: top; background-color: rgb(255, 252, 214);\" data-mce-style=\"outline: none; width: 95px; text-align: left; vertical-align: top; background-color: #fffcd6;\">SmartFTP</td><td style=\"outline: none; width: 173px; text-align: left; vertical-align: top; background-color: rgb(255, 252, 214);\" data-mce-style=\"outline: none; width: 173px; text-align: left; vertical-align: top; background-color: #fffcd6;\">Windows</td><td style=\"outline: none; width: 212px; text-align: left; vertical-align: top; background-color: rgb(255, 252, 214);\" data-mce-style=\"outline: none; width: 212px; text-align: left; vertical-align: top; background-color: #fffcd6;\"><a>https:/<wbr>/<wbr>www.smartftp.com</a></td><td style=\"outline: none; width: 194px; text-align: left; vertical-align: top; background-color: rgb(255, 252, 214);\" data-mce-style=\"outline: none; width: 194px; text-align: left; vertical-align: top; background-color: #fffcd6;\">Free download</td></tr><tr><td style=\"outline: none; width: 95px; text-align: left; vertical-align: top; background-color: rgb(255, 253, 233);\" data-mce-style=\"outline: none; width: 95px; text-align: left; vertical-align: top; background-color: #fffde9;\">CuteFTP</td><td style=\"outline: none; width: 173px; text-align: left; vertical-align: top; background-color: rgb(255, 253, 233);\" data-mce-style=\"outline: none; width: 173px; text-align: left; vertical-align: top; background-color: #fffde9;\">Windows, Mac</td><td style=\"outline: none; width: 212px; text-align: left; vertical-align: top; background-color: rgb(255, 253, 233);\" data-mce-style=\"outline: none; width: 212px; text-align: left; vertical-align: top; background-color: #fffde9;\"><a>https:/<wbr>/<wbr>www.cuteftp.com</a></td><td style=\"outline: none; width: 194px; text-align: left; vertical-align: top; background-color: rgb(255, 253, 233);\" data-mce-style=\"outline: none; width: 194px; text-align: left; vertical-align: top; background-color: #fffde9;\">Free trial download, academic pricing available</td></tr><tr><td style=\"outline: none; width: 95px; text-align: left; vertical-align: top; background-color: rgb(255, 252, 214);\" data-mce-style=\"outline: none; width: 95px; text-align: left; vertical-align: top; background-color: #fffcd6;\">WS_FTP</td><td style=\"outline: none; width: 173px; text-align: left; vertical-align: top; background-color: rgb(255, 252, 214);\" data-mce-style=\"outline: none; width: 173px; text-align: left; vertical-align: top; background-color: #fffcd6;\">Windows</td><td style=\"outline: none; width: 212px; text-align: left; vertical-align: top; background-color: rgb(255, 252, 214);\" data-mce-style=\"outline: none; width: 212px; text-align: left; vertical-align: top; background-color: #fffcd6;\"><a>https:/<wbr>/<wbr>www.ipswitch.com</a></td><td style=\"outline: none; width: 194px; text-align: left; vertical-align: top; background-color: rgb(255, 252, 214);\" data-mce-style=\"outline: none; width: 194px; text-align: left; vertical-align: top; background-color: #fffcd6;\">Free trial download</td></tr></tbody></table>` 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/