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

r"
"
gmix

Test String

Code Generator

Generated Code

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r""" (\b(\b(?:times|some time|any time))\b|\b(1[0-9]th)\b|\b([2-3]0th)\b|\b([2-3]?1st)\b|\b(2?2nd)\b|\b(2?3rd)\b|\b(2?[4-9]th)\b|\b((?:(?:1[0-9]|2[0-4]|0?[0-9])(?:(?:[ ]?(?:or|[,/-]|to|and)[ ]?))){0,3}((?:1[0-9]|2[0-4]|0?[0-9]))((?:[ ]?[\:\.][ ]?)([0-5][0-9])|(?:[ ]?[ap]m|[ ]?o\'?[ ]?clock)|(?:[ ]?(?: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)){1,3})\b|\b(january)\b|\b(jan\b)\b|\b(february)\b|\b(feb\b)\b|\b(march)\b|\b(mar\b)\b|\b(april)\b|\b(apr\b)\b|\b(may\b)\b|\b(june)\b|\b(jun\b)\b|\b(july)\b|\b(jul\b)\b|\b(august)\b|\b(aug\b)\b|\b(september)\b|\b(sept?)\b|\b(october)\b|\b(oct\b)\b|\b(november)\b|\b(nov\b)\b|\b(december)\b|\b(dec\b)\b|\b(\bnext\b)\b|\b(tomorr?ow (?:afternoon|morning|\bmorn\b|evening|\beve\b|midd?ay))\b|\b(\bfew\b)\b|\b(\bafter\b)\b|\b(last (?:not Last [week] of [month|year]))\b|\b([Mm]onday)\b|\b(year)\b|\b(afternoon)\b|\b(hours?)\b|\b(\bnoon\b)\b|\b(lunch)\b|\b(weekend)\b|\b(seconds)\b|\b(meeting)\b|\b(\bfirst\b)\b|\b(\bseveral\b)\b|\b(\bbefore\b)\b|\b(the other [wee|day|month|year])\b|\b([Mm]on\b)\b|\b(month)\b|\b(morning)\b|\b(minutes?)\b|\b(midnight)\b|\b(brunch)\b|\b(today)\b|\b(\bsecs\b)\b|\b(call)\b|\b(\bsecond\b)\b|\b(\bcouple\b)\b|\b(\bbetween\b)\b|\b(^^Regex less opening condition)\b|\b([Tt]uesday)\b|\b(\bweek\b)\b|\b(\bmorn\b)\b|\b(\bdays\b)\b|\b(midday)\b|\b(dinner)\b|\b(∆now)\b|\b(minutes)\b|\b(phone call)\b|\b(\bthird\b)\b|\b(\bsome\b)\b|\b(in ?-? ?between)\b|\b([Tt]ue\b)\b|\b(\bday\b)\b|\b(evening)\b|\b(fou?rtnights)\b|\b(breakfast)\b|\b(tomorrow)\b|\b(\bmins\b)\b|\b(conference call)\b|\b(\bfourth\b)\b|\b(\bmany\b)\b|\b([Ww]ednesday)\b|\b(fou?rtnight)\b|\b(\beve\b)\b|\b(years)\b|\b(\bmns\b)\b|\b(coffee)\b|\b(following)\b|\b(\bin a)\b|\b([Ww]eds?)\b|\b(days∆)\b|\b(midd?ay)\b|\b(months)\b|\b(hours)\b|\b(\bcoming\b)\b|\b([Tt]hursday)\b|\b(weeks)\b|\b(\bhrs\b)\b|\b(\blast\b)\b|\b([1-9][0-9])\b|\b([Tt]hur)\b|\b(\bthis\b)\b|\b([Ff]riday)\b|\b([Ff]ri\b)\b|\b([Ss]aturday)\b|\b(meet)\b|\b([Ss]at\b)\b|\b(phone)\b|\b([Ss]unday)\b|\b([Ss]un\b)\b|\b(Enhanced Version For Martin. +ve Look Behinds and limited scope for the number of minutes in the secon number. 5,10,15,20,30,45 mins past the hour)\b|\b(Enhanced Version For Martin. +ve Look Behinds)\b|\b(\bPS?T\b)\b|\b(\bGMT\b)\b|\b(\b∆USA\b)\b|\b(\b∆US\b)\b|\b(\bET\b)\b|\b(\bBST\b)\b|\b(\b∆UK\b)\b|\b(\bUK ?[Tt]ime\b)\b|\b(\b[Ee]astern [Tt]ime\b)\b|\b(\b[Pp]acific [Tt]ime\b)\b|\b(\b[Cc]entral [Tt]ime\b)\b|\b(\bACDT\b)\b|\b(\bACST\b)\b|\b(\bACT\b)\b|\b(\bADT\b)\b|\b(\bAEDT\b)\b|\b(\bAEST\b)\b|\b(\bAFT\b)\b|\b(\bAKDT\b)\b|\b(\bAKST\b)\b|\b(\bAMST\b)\b|\b(\bAMT\b)\b|\b(\bART\b)\b|\b(\bAST\b)\b|\b(\bAWDT\b)\b|\b(\bAWST\b)\b|\b(\bAZOST\b)\b|\b(\bAZT\b)\b|\b(\bBDT\b)\b|\b(\bBIOT\b)\b|\b(\bBRST\b)\b|\b(\bBRT\b)\b|\b(\bBTT\b)\b|\b(\bCCT\b)\b|\b(\bCDT\b)\b|\b(\bCEDT\b)\b|\b(\bCEST\b)\b|\b(\bCET\b)\b|\b(\bCHADT\b)\b|\b(\bCHAST\b)\b|\b(\bCHOT\b)\b|\b(\bChST\b)\b|\b(\bCHUT\b)\b|\b(\bCIST\b)\b|\b(\bCIT\b)\b|\b(\bCKT\b)\b|\b(\bCLST\b)\b|\b(\bCLT\b)\b|\b(\bCOT\b)\b|\b(\bCST\b)\b|\b(\bCT\b)\b|\b(\bCVT\b)\b|\b(\bCWST\b)\b|\b(\bCXT\b)\b|\b(\bDAVT\b)\b|\b(\bDDUT\b)\b|\b(\bDFT\b)\b|\b(\bEASST\b)\b|\b(\bECT\b)\b|\b(\bEDT\b)\b|\b(\bEEDT\b)\b|\b(\bEEST\b)\b|\b(\bEET\b)\b|\b(\bEGST\b)\b|\b(\bEGT\b)\b|\b(\bEIT\b)\b|\b(\bEST\b)\b|\b(\bFET\b)\b|\b(\bFJT\b)\b|\b(\bFKST\b)\b|\b(\bFKT\b)\b|\b(\bFNT\b)\b|\b(\bGALT\b)\b|\b(\bGAMT\b)\b|\b(\bGFT\b)\b|\b(\bGILT\b)\b|\b(\bGIT\b)\b|\b(\bGST\b)\b|\b(\bGYT\b)\b|\b(\bHADT\b)\b|\b(\bHAEC\b)\b|\b(\bHAST\b)\b|\b(\bHKT\b)\b|\b(\bHMT\b)\b|\b(\bHOVT\b)\b|\b(\bHST\b)\b|\b(\bIBST\b)\b|\b(\bICT\b)\b|\b(\bIDT\b)\b|\b(\bIRDT\b)\b|\b(\bIRKT\b)\b|\b(\bIRST\b)\b|\b(\bIST\b)\b|\b(\bJST\b)\b|\b(\bKGT\b)\b|\b(\bKOST\b)\b|\b(\bKRAT\b)\b|\b(\bKST\b)\b|\b(\bLHST\b)\b|\b(\bLINT\b)\b|\b(\bMAGT\b)\b|\b(\bMART\b)\b|\b(\bMAWT\b)\b|\b(\bMDT\b)\b|\b(\bMET\b)\b|\b(\bMEST\b)\b|\b(\bMHT\b)\b|\b(\bMIST\b)\b|\b(\bMMT\b)\b|\b(\bMSK\b)\b|\b(\bMST\b)\b|\b(\bMUT\b)\b|\b(\bMVT\b)\b|\b(\bMYT\b)\b|\b(\bNCT\b)\b|\b(\bNDT\b)\b|\b(\bNFT\b)\b|\b(\bNPT\b)\b|\b(\bNST\b)\b|\b(\bNT\b)\b|\b(\bNUT\b)\b|\b(\bNZDT\b)\b|\b(\bNZST\b)\b|\b(\bOMST\b)\b|\b(\bORAT\b)\b|\b(\bPDT\b)\b|\b(\bPETT\b)\b|\b(\bPGT\b)\b|\b(\bPHOT\b)\b|\b(\bPKT\b)\b|\b(\bPMDT\b)\b|\b(\bPMST\b)\b|\b(\bPONT\b)\b|\b(\bPST\b)\b|\b(\bPYST\b)\b|\b(\bPYT\b)\b|\b(\bRET\b)\b|\b(\bROTT\b)\b|\b(\bSAKT\b)\b|\b(\bSAMT\b)\b|\b(\bSAST\b)\b|\b(\bSBT\b)\b|\b(\bSCT\b)\b|\b(\bSGT\b)\b|\b(\bSLST\b)\b|\b(\bSRET\b)\b|\b(\bSRT\b)\b|\b(\bSST\b)\b|\b(\bSYOT\b)\b|\b(\bTAHT\b)\b|\b(\bTHA\b)\b|\b(\bTFT\b)\b|\b(\bTJT\b)\b|\b(\bTKT\b)\b|\b(\bTLT\b)\b|\b(\bTMT\b)\b|\b(\bTOT\b)\b|\b(\bTVT\b)\b|\b(\bUCT\b)\b|\b(\bULAT\b)\b|\b(\bUSZ1\b)\b|\b(\bUTC\b)\b|\b(\bUYST\b)\b|\b(\bUYT\b)\b|\b(\bUZT\b)\b|\b(\bVET\b)\b|\b(\bVLAT\b)\b|\b(\bVOLT\b)\b|\b(\bVOST\b)\b|\b(\bVUT\b)\b|\b(\bWAKT\b)\b|\b(\bWAST\b)\b|\b(\bWAT\b)\b|\b(\bWEDT\b)\b|\b(\bWEST\b)\b|\b(\bWET\b)\b|\b(\bWST\b)\b|\b(\bYAKT\b)\b|\b(\bUK\b)\b|\b(\bUS\b)\b|\b(\bPT\b)\b|\b(\bUK Time\b)\b|\b(\bUKTime\b)\b|\b(\bUK time\b)\b|\b(\bUKtime\b)\b|\b(\bEastern Time\b)\b|\b(\bEastern time\b)\b|\b(\beastern time\b)\b|\b(\bPacific Time\b)\b|\b(\bPacific time\b)\b|\b(\bpacific time\b)\b|\b(\bCentral Time\b)\b|\b(\bCentral time\b)\b|\b(\bcentral time\b)\b|\b(\bEasternTime\b)\b|\b(\bEasterntime\b)\b|\b(Spanish time)\b|\b(Atlanta time)\b) """ test_str = ("NEW TIME MATCHING REGEX\n" "*** REGEX 1: LONELY NUMBERS ***\n" "12 or 3pm\n" "4/5CET\n" "5-6pm\n" "2,4,5pm\n" "1,3 or 6pm\n" "OK. 1,2,3 and 5pm are available\n" "12pm or 3pm <Shouldn't match \"or\"\n\n" "#Military times\n" "1200 or 1300.\n" "1100,1300 or 1400.\n" "121212121212121212 <don't match\n\n" "*** REGEX 2: BASICS ***\n" "1\n" "11am or 2pm\n" "12pm\n" "12 CET\n" "12pm CET\n" "12.32pm\n" "14 pm\n" "10.00?\n" "0.15\n" "3 : 34\n" "10 53\n" "00.15\n" "at3.00?\n" "10amis good for me\n" " 4 oclock\n" "2o'clock\n" "2 o clock\n" "yes,3 am\n" "12.50 GBP\n" "USD 4.00\n\n" "£12.50\n" "10.93?\n" "00000\n" "0000-559\n" "00001\n\n\n\n\n" "00001\n" "00001\n" "01300\n" "01700\n" "from 2 - 6\n" "there is about 3 of them\n" "Not sure, maybe 14 apples?\n" "how about 10 tomorrow? << should fail\n" "10 tomorrow?\n" "about £23.00\n\n\n" "10,11 or 12\n" "10, 11 or 2?\n" "10 or 12?\n" "10 or my place?\n" "1030 or 1130\n" "10.30 or 12?\n" "10 and 11 work\n" "10, 11, 12th?\n\n" "1,000\n") matches = re.finditer(regex, test_str, re.MULTILINE | re.IGNORECASE | re.VERBOSE) for matchNum, match in enumerate(matches, start=1): print ("Match {matchNum} was found at {start}-{end}: {match}".format(matchNum = matchNum, start = match.start(), end = match.end(), match = match.group())) for groupNum in range(0, len(match.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = match.start(groupNum), end = match.end(groupNum), group = match.group(groupNum))) # Note: for Python 2.7 compatibility, use ur"" to prefix the regex and u"" to prefix the test string and substitution.

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 Python, please visit: https://docs.python.org/3/library/re.html