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

/
/

Test String

Code Generator

Generated Code

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`^AL\d{10}[0-9A-Z]{16}$|^AD\d{10}[0-9A-Z]{12}$|^AT\d{18}$|^BH\d{2}[A-Z]{4}[0-9A-Z]{14}$|^BE\d{14}$|^BA\d{18}$|^BG\d{2}[A-Z]{4}\d{6}[0-9A-Z]{8}$|^HR\d{19}$|^CY\d{10}[0-9A-Z]{16}$|^CZ\d{22}$|^DK\d{16}$|^FO\d{16}$|^GL\d{16}$|^DO\d{2}[0-9A-Z]{4}\d{20}$|^EE\d{18}$|^FI\d{16}$|^FR\d{12}[0-9A-Z]{11}\d{2}$|^GE\d{2}[A-Z]{2}\d{16}$|^DE\d{20}$|^GI\d{2}[A-Z]{4}[0-9A-Z]{15}$|^GR\d{9}[0-9A-Z]{16}$|^HU\d{26}$|^IS\d{24}$|^IE\d{2}[A-Z]{4}\d{14}$|^IL\d{21}$|^IT\d{2}[A-Z]\d{10}[0-9A-Z]{12}$|^[A-Z]{2}\d{5}[0-9A-Z]{13}$|^KW\d{2}[A-Z]{4}22!$|^LV\d{2}[A-Z]{4}[0-9A-Z]{13}$|^LB\d{6}[0-9A-Z]{20}$|^LI\d{7}[0-9A-Z]{12}$|^LT\d{18}$|^LU\d{5}[0-9A-Z]{13}$|^MK\d{5}[0-9A-Z]{10}\d{2}$|^MT\d{2}[A-Z]{4}\d{5}[0-9A-Z]{18}$|^MR13\d{23}$|^MU\d{2}[A-Z]{4}\d{19}[A-Z]{3}$|^MC\d{12}[0-9A-Z]{11}\d{2}$|^ME\d{20}$|^NL\d{2}[A-Z]{4}\d{10}$|^NO\d{13}$|^PL\d{10}[0-9A-Z]{,16}n$|^PT\d{23}$|^RO\d{2}[A-Z]{4}[0-9A-Z]{16}$|^SM\d{2}[A-Z]\d{10}[0-9A-Z]{12}$|^SA\d{4}[0-9A-Z]{18}$|^RS\d{20}$|^SK\d{22}$|^SI\d{17}$|^ES\d{22}$|^SE\d{22}$|^CH\d{7}[0-9A-Z]{12}$|^TN59\d{20}$|^TR\d{7}[0-9A-Z]{17}$|^AE\d{21}$|^GB\d{2}[A-Z]{4}\d{14}$`) var str = `NL39INGB0044332211` 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/