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 = '/\b\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}\b/mi'; $str = 'DMA-WS -> Requested name does not exist DCTM_FSS -> Requested name does not exist CHSA0884 -> Requested name does not exist CHWU2550101 -> Requested name does not exist LPM.CSINTRA.NET -> Requested name does not exist WPAD -> Requested name does not exist WWW.FOXNEWS.COM -> Requested name does not exist USWT2507857 -> Requested name does not exist GBLADHEDANI -> Requested name does not exist WWW.GOOGLE.COM -> Requested name does not exist WWW.ESPN.COM -> Requested name does not exist T.CO -> Requested name does not exist DPM.DEMDEX.NET -> Requested name does not exist US-U.OPENX.NET -> Requested name does not exist SYNC.1RX.IO -> Requested name does not exist IB.ADNXS.COM -> Requested name does not exist WWW.YOUTUBE.COM -> Requested name does not exist CDN.KRXD.NET -> Requested name does not exist APIS.GOOGLE.COM -> Requested name does not exist CDN.DIGITRU.ST -> Requested name does not exist ID.GOOGLE.COM -> Requested name does not exist GEO.MOATADS.COM -> Requested name does not exist VARS.HOTJAR.COM -> Requested name does not exist ACDN.ADNXS.COM -> Requested name does not exist * -> 0.33.0.1 S7.ADDTHIS.COM -> Requested name does not exist C.BETRAD.COM -> Requested name does not exist OGS.GOOGLE.COM -> Requested name does not exist ML314.COM -> Requested name does not exist D.AGKN.COM -> Requested name does not exist SNYC17P15002 -> Requested name does not exist SC.IASDS01.COM -> Requested name does not exist API.RLCDN.COM -> Requested name does not exist SSL.GSTATIC.COM -> Requested name does not exist SYNC.TEADS.TV -> Requested name does not exist TRC.TABOOLA.COM -> Requested name does not exist SF.SYMCD.COM -> Requested name does not exist MB.MOATADS.COM -> Requested name does not exist SNYC50P02006 -> Requested name does not exist GBLADHEDANI -> 255.255.255.255 C1.ADFORM.NET -> Requested name does not exist DISQUS.COM -> Requested name does not exist EB2.3LIFT.COM -> Requested name does not exist PORTAL.ADP.COM -> Requested name does not exist STATIC.ADP.COM -> Requested name does not exist CTI.W55C.NET -> Requested name does not exist WWW.BING.COM -> Requested name does not exist MY.ADP.COM -> Requested name does not exist DTS.INNOVID.COM -> Requested name does not exist GU.DYNTRK.COM -> Requested name does not exist TAGS.TIQCDN.COM -> Requested name does not exist SYNC.JIVOX.COM -> Requested name does not exist RP.GWALLET.COM -> Requested name does not exist FED.ADP.COM -> Requested name does not exist AP.LIJIT.COM -> Requested name does not exist I.LIADM.COM -> Requested name does not exist RTAX.CRITEO.COM -> Requested name does not exist SYNC.BFMIO.COM -> Requested name does not exist A.RFIHUB.COM -> Requested name does not exist T.A3CLOUD.NET -> Requested name does not exist GNYC11P21005 -> Requested name does not exist SITES.CHASE.COM -> Requested name does not exist LIVE.REZYNC.COM -> Requested name does not exist RF15.CHASE.COM -> Requested name does not exist ONLINE.ADP.COM -> Requested name does not exist Z.MOATADS.COM -> Requested name does not exist DISQUSADS.COM -> Requested name does not exist RTB.GUMGUM.COM -> Requested name does not exist PIPPIO.COM -> Requested name does not exist X.BIDSWITCH.NET -> Requested name does not exist B.ADMEDIA.COM -> Requested name does not exist JS.STRIPE.COM -> Requested name does not exist EC.WALKME.COM -> Requested name does not exist IESS.HGS-BS.COM -> Requested name does not exist J.MRPDATA.NET -> Requested name does not exist 15.TABOOLA.COM -> Requested name does not exist MIDAS.CHASE.COM -> Requested name does not exist WWW.HITC.COM -> Requested name does not exist S0.2MDN.NET -> Requested name does not exist SPRI17P10001 -> Requested name does not exist PLAY.GOOGLE.COM -> Requested name does not exist S8T.TEADS.TV -> Requested name does not exist WWW.CHASE.COM -> Requested name does not exist SPRI50B02006 -> 169.43.126.22 STUN.NAS.NET -> Requested name does not exist WWW.VIZURY.COM -> Requested name does not exist ESPN.COM -> Requested name does not exist GMIL59B02001 -> Requested name does not exist G.JWPSRV.COM -> Requested name does not exist SCDN.CXENSE.COM -> Requested name does not exist NT AUTHORITY -> Requested name does not exist EB.WBMASON.COM -> Requested name does not exist GMIL59P02001 -> Requested name does not exist DE.TYNT.COM -> Requested name does not exist CDN.WALKME.COM -> Requested name does not exist PX.MOATADS.COM -> Requested name does not exist ADS.YAHOO.COM -> Requested name does not exist STUN.VEOH.COM -> Requested name does not exist WWW.SEC.GOV -> Requested name does not exist HBEVENTS.1RX.IO -> Requested name does not exist A-NJ.1RX.IO -> Requested name does not exist R.3GL.NET -> Requested name does not exist WWW.DIANOMI.COM -> Requested name does not exist STUN.VOXOX.COM -> Requested name does not exist BIDDER.RTK.IO -> Requested name does not exist L.SHARETHIS.COM -> Requested name does not exist S.NTV.IO -> Requested name does not exist T.SHARETHIS.COM -> Requested name does not exist BAM.NR-DATA.NET -> Requested name does not exist STUN.JUMBLO.COM -> Requested name does not exist UM2.EQADS.COM -> Requested name does not exist CK.CONNATIX.COM -> Requested name does not exist WWW.CNN.COM -> Requested name does not exist WWW2.BING.COM -> Requested name does not exist RTB.NUI.MEDIA -> Requested name does not exist GEO2.ADOBE.COM -> Requested name does not exist NT SERVICE -> Requested name does not exist WWW.JETBLUE.COM -> Requested name does not exist WWW.PAYPAL.COM -> Requested name does not exist STUN.2TALK.COM -> Requested name does not exist OUT.REDDIT.COM -> Requested name does not exist M.STRIPE.COM -> Requested name does not exist CONNEXITY.NET -> Requested name does not exist STUN.WWDL.NET -> Requested name does not exist CDN.W55C.NET -> Requested name does not exist THOR.RTK.IO -> Requested name does not exist 1898.DEMDEX.NET -> Requested name does not exist RTR.INNOVID.COM -> Requested name does not exist SPNQ15P01001 -> Requested name does not exist CDN.UNID.GO.COM -> Requested name does not exist PSA.CARAMBO.LA -> Requested name does not exist UNID.GO.COM -> Requested name does not exist T.PUBMATIC.COM -> Requested name does not exist WWW.MSN.COM -> Requested name does not exist WWW.AMAZON.COM -> Requested name does not exist IMG.3LIFT.COM -> Requested name does not exist ESPN.GO.COM -> Requested name does not exist WWW.NYTIMES.COM -> Requested name does not exist PAY.GOOGLE.COM -> Requested name does not exist W.USABILLA.COM -> Requested name does not exist WWW.TEST.COM -> Requested name does not exist ROVER.EBAY.COM -> Requested name does not exist NB.FIDELITY.COM -> Requested name does not exist WWW.GSTATIC.COM -> Requested name does not exist RS.GWALLET.COM -> Requested name does not exist CDN8.VIZURY.COM -> Requested name does not exist LOG.GO.COM -> Requested name does not exist SNYC14P21003 -> Requested name does not exist AURA.ALIGHT.COM -> Requested name does not exist WWW.WSJ.COM -> Requested name does not exist EU.DOCUSIGN.NET -> Requested name does not exist PIPE.SKYPE.COM -> Requested name does not exist U.OPENX.NET -> Requested name does not exist A.TEADS.TV -> Requested name does not exist AX.LEMNISK.CO -> Requested name does not exist CAL.ESPN.COM -> Requested name does not exist AD.TURN.COM -> Requested name does not exist APP.HUBSPOT.COM -> Requested name does not exist SNYC14P21001 -> Requested name does not exist T.LKQD.NET -> Requested name does not exist GPRI11P21001 -> 169.49.98.15 API.ALIGHT.COM -> Requested name does not exist CP.HDFCBANK.COM -> Requested name does not exist SNYC11P21003 -> 169.37.57.173 SPRI10P00054 -> 169.35.89.162 WWW.YELP.COM -> Requested name does not exist SAML.ALIGHT.COM -> Requested name does not exist VCDN.ADNXS.COM -> Requested name does not exist GLON11P10043 -> Requested name does not exist PIX.ADRTA.COM -> Requested name does not exist CWS.CONVIVA.COM -> Requested name does not exist A.ESPNCDN.COM -> Requested name does not exist GNYC11P21003 -> Requested name does not exist SYNC.RTK.IO -> Requested name does not exist OTF.MSN.COM -> Requested name does not exist ADS.ADAP.TV -> Requested name does not exist SECURE.FLYR.IO -> Requested name does not exist WWW.EENADU.NET -> Requested name does not exist AEXP.DEMDEX.NET -> Requested name does not exist VMG.HOST -> Requested name does not exist BEA4.CNN.COM -> Requested name does not exist TAG-NJ.1RX.IO -> Requested name does not exist CDN.REVJET.COM -> Requested name does not exist ONETAG-SYS.COM -> Requested name does not exist WWW.WCPSS.NET -> Requested name does not exist SAM.MSN.COM -> Requested name does not exist PX.OWNERIQ.NET -> Requested name does not exist DSP.V.FWMRM.NET -> Requested name does not exist XTR.CARAMBO.LA -> Requested name does not exist WWW.CDN-NET.COM -> Requested name does not exist WWW.TAMGRT.COM -> Requested name does not exist S.ADZMATH.COM -> Requested name does not exist 1179.XG4KEN.COM -> Requested name does not exist CARS.USNEWS.COM -> Requested name does not exist EU.HIPEROS.COM -> Requested name does not exist MCPM.MARKIT.COM -> Requested name does not exist ATT.INQ.COM -> Requested name does not exist USV03754259 -> 169.49.6.226 WWW.MARVAL.COM -> Requested name does not exist I.YTIMG.COM -> Requested name does not exist '; 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