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

/
/
gmi

Test String

Code Generator

Language

Generated Code

$re = '/((?:[ ]|^|[^\d\.\:\-\r\n$£])((?:1[0-9]|2[0-4]|0?[1-9]|00|one|two|three|four|five|six|seven|eight|nine|ten|eleven|twelve)[ ]?[\:\. ]?[ ]?(?:[0-5][0-9]|fifteen|thirty|fou?rty ?five)(?:[ ]?(?:am|pm)|[ ]?o\'?[ ]?clock))(?:\b|$|,\b)|(?:[ ]|^|[^\d\.\:\-\r\n$£])(((?:1[0-9]|2[0-4]|0?[1-9]|00|one|two|three|four|five|six|seven|eight|nine|ten|eleven|twelve)(?:[ ]?(?:am|pm))|[ ]?o\'?[ ]?clock))(?:\b|$|,\b)|(?:[ ]|^|[^\d\.\:\-\r\n$£])((?:1[0-9]|2[0-4]|0?[1-9]|00|one|two|three|four|five|six|seven|eight|nine|ten|eleven|twelve)[ ]?[\:\. ][ ]?(?:[0-5][0-9]|fifteen|thirty|fou?rty ?five)(?:\b|$|,\b))|(?:[ ]|^|[^\d\.\:\-\r\n$£])((?:1[0-9]|2[0-4]|0?[1-9]|00) ?(?:PS?T|GMT|∆USA|∆US|ET|BST|∆UK|UK ?[Tt]ime|[Ee]astern [Tt]ime|[Pp]acific [Tt]ime|[Cc]entral [Tt]ime|∆UTC|ACDT|ACST|ACT|ACT|ADT|AEDT|AEST|AFT|AKDT|AKST|AMST|AMT|AMT|ART|AST|AST|AWDT|AWST|AZOST|AZT|BDT|BDT|BIOT|BRST|BRT|BST|BST|BST|BTT|CCT|CDT|CDT|CEDT|CEST|CET|CHADT|CHAST|CHOT|ChST|CHUT|CIST|CIT|CKT|CLST|CLT|COT|CST|CST|CST|CST|CST|CT|CVT|CWST|CXT|DAVT|DDUT|DFT|EASST|ECT|ECT|EDT|EEDT|EEST|EET|EGST|EGT|EIT|EST|EST|FET|FJT|FKST|FKST|FKT|FNT|GALT|GAMT|GFT|GILT|GIT|GMT|GST|GST|GYT|HADT|HAEC|HAST|HKT|HMT|HOVT|HST|IBST|ICT|IDT|IRDT|IRKT|IRST|IST|IST|IST|JST|KGT|KOST|KRAT|KST|LHST|LHST|LINT|MAGT|MART|MAWT|MDT|MET|MEST|MHT|MIST|MMT|MSK|MST|MST|MST|MUT|MVT|MYT|NCT|NDT|NFT|NPT|NST|NT|NUT|NZDT|NZST|OMST|ORAT|PDT|PETT|PGT|PHOT|PKT|PMDT|PMST|PONT|PST|PST|PYST|PYT|RET|ROTT|SAKT|SAMT|SAST|SBT|SCT|SGT|SLST|SRET|SRT|SST|SST|SYOT|TAHT|THA|TFT|TJT|TKT|TLT|TMT|TOT|TVT|ULAT|USZ1|UYST|UYT|UZT|VET|VLAT|VOLT|VOST|VUT|WAKT|WAST|WAT|WEDT|WEST|WET|WST|YAKT))\b)/mi'; $str = '4pm 12:00 4 CET 17 UK Time 1200pm 12pm 14.00 15.00pm 33 4pm 4 pm 4:30pm 3/5/7 Mon Tue Next Tue '; preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0); // Print the entire match result var_dump($matches);

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 PHP, please visit: http://php.net/manual/en/ref.pcre.php