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

use strict; my $str = ''; my $regex = qr/(?<CountryCodes>^\b(AF|AX|AL|DZ|AS|AD|AO|AI|AQ|AG|AR|AM|AW|AU|AT|AZ|BS|BH|BD|BB|BY|BE|BZ|BJ|BM|BT|BO|BQ|BA|BW|BV|BR|IO|BN|BG|BF|BI|KH|CM|CA|CV|KY|CF|TD|CL|CN|CX|CC|CO|KM|CG|CD|CK|CR|CI|HR|CU|CW|CY|CZ|DK|DJ|DM|DO|EC|EG|SV|GQ|ER|EE|ET|EU|FK|FO|FJ|FI|FR|GF|PF|TF|GA|GM|GE|DE|GH|GI|GR|GL|GD|GP|GU|GT|GG|GN|GW|GY|HT|HM|VA|HN|HK|HU|IS|IN|ID|IR|IQ|IE|IM|IL|IT|JM|JP|JE|JO|KZ|KE|KI|KP|KR|KW|KG|LA|LV|LB|LS|LR|LY|LI|LT|LU|MO|MK|MG|MW|MY|MV|ML|MT|MH|MQ|MR|MU|YT|MX|FM|MD|MC|MN|ME|MS|MA|MZ|MM|NA|NR|NP|NL|NC|NZ|NI|NE|NG|NU|NF|MP|NO|OM|PK|PW|PS|PA|PG|PY|PE|PH|PN|PL|PT|PR|QA|RE|RO|RU|RW|BL|SH|KN|LC|MF|PM|VC|WS|SM|ST|SA|SN|RS|SC|SL|SG|SX|SK|SI|SB|SO|ZA|GS|SS|ES|LK|SD|SR|SJ|SZ|SE|CH|SY|TW|TJ|TZ|TH|TL|TG|TK|TO|TT|TN|TR|TM|TC|TV|UG|UA|AE|GB|US|UM|UY|UZ|VU|VE|VN|VG|VI|WF|EH|YE|ZM|ZW|AFG|ALB|DZA|ASM|AND|AGO|AIA|ATA|ATG|ARG|ARM|ABW|AUS|AUT|AZE|BHS|BHR|BGD|BRB|BLR|BEL|BLZ|BEN|BMU|BTN|BOL|BIH|BWA|BVT|BRA|IOT|VGB|BRN|BGR|BFA|BDI|KHM|CMR|CAN|CPV|CYM|CAF|TCD|CHL|CHN|CXR|CCK|COL|COM|COD|COG|COK|CRI|CIV|CUB|CYP|CZE|DNK|DJI|DMA|DOM|ECU|EGY|SLV|GNQ|ERI|EST|ETH|FRO|FLK|FJI|FIN|FRA|GUF|PYF|ATF|GAB|GMB|GEO|DEU|GHA|GIB|GRC|GRL|GRD|GLP|GUM|GTM|GIN|GNB|GUY|HTI|HMD|VAT|HND|HKG|HRV|HUN|ISL|IND|IDN|IRN|IRQ|IRL|ISR|ITA|JAM|JPN|JOR|KAZ|KEN|KIR|PRK|KOR|KWT|KGZ|LAO|LVA|LBN|LSO|LBR|LBY|LIE|LTU|LUX|MAC|MKD|MDG|MWI|MYS|MDV|MLI|MLT|MHL|MTQ|MRT|MUS|MYT|MEX|FSM|MDA|MCO|MNG|MSR|MAR|MOZ|MMR|NAM|NRU|NPL|ANT|NLD|NCL|NZL|NIC|NER|NGA|NIU|NFK|MNP|NOR|OMN|PAK|PLW|PSE|PAN|PNG|PRY|PER|PHL|PCN|POL|PRT|PRI|QAT|REU|ROU|RUS|RWA|SHN|KNA|LCA|SPM|VCT|WSM|SMR|STP|SAU|SEN|SCG|SYC|SLE|SGP|SVK|SVN|SLB|SOM|ZAF|SGS|ESP|LKA|SDN|SUR|SJM|SWZ|SWE|CHE|SYR|TWN|TJK|TZA|THA|TLS|TGO|TKL|TON|TTO|TUN|TUR|TKM|TCA|TUV|VIR|UGA|UKR|ARE|GBR|UMI|USA|URY|UZB|VUT|VEN|VNM|WLF|ESH|YEM|ZMB|ZWE)\b)/mp; if ( $str =~ /$regex/g ) { print "Whole match is ${^MATCH} and its start/end positions can be obtained via \$-[0] and \$+[0]\n"; # print "Capture Group 1 is $1 and its start/end positions can be obtained via \$-[1] and \$+[1]\n"; # print "Capture Group 2 is $2 ... and so on\n"; } # ${^POSTMATCH} and ${^PREMATCH} are also available with the use of '/p' # Named capture groups can be called via $+{name}

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 Perl, please visit: http://perldoc.perl.org/perlre.html