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
Processing...

Test String

Code Generator

Language

Generated Code

const regex = /\bsrc=1.1.1[4-5]{0,1}.[0-9]{0,3}\b.*?\bdeviceOutboundInterface=DOI-Out\b/; // Alternative syntax using RegExp constructor // const regex = new RegExp('\\bsrc=1.1.1[4-5]{0,1}.[0-9]{0,3}\\b.*?\\bdeviceOutboundInterface=DOI-Out\\b', '') const str = `Jul 21 11:59:57 Firewall-Name-Removed CEF:0|Fortinet|FortiGate-<removed>|1.2.3,build1111 (GA)|0000000013|forward traffic accept|5|start=Jul 21 2022 11:59:57 logver=604091966 deviceExternalId=FG9H5A3J1789999 dvchost=Firewall-Name-Removed ad.vd=root ad.eventtime=1111111111111111111 ad.tz=-9999 ad.logid=0000000013 cat=traffic ad.subtype=forward deviceSeverity=notice src=1.1.1.1 shost=RandomHost1 spt=62119 deviceInboundInterface=DII-Out ad.srcintfrole=lan ad.srcssid=SSID Has Been Removed ad.apsn=ABC123D ad.ap=CHL-07 ad.channel=157 ad.radioband=802.11ac n-only ad.signal=-40 ad.snr=55 dst=2.2.2.2 dpt=53 deviceOutboundInterface=DOI-Out ad.dstintfrole=undefined ad.srccountry=Reserved ad.dstcountry=CountryRemoved externalID=123456789 proto=00 act=accept ad.policyid=000 ad.policytype=policy ad.poluuid=UUID-Removed ad.policyname=policy_name_removed app=DNS ad.trandisp=noop ad.appid=16195 ad.app=DNS ad.appcat=Network.Service ad.apprisk=elevated ad.applist=UTM Name - Removed ad.duration=180 out=0 in=205 ad.sentpkt=0 ad.rcvdpkt=1 ad.utmaction=allow ad.countdns=1 ad.osname=Windows ad.srcswversion=10 ad.mastersrcmac=<MAC removed> ad.srcmac=<MAC removed> ad.srcserver=0 tz="-9999"`; // Reset `lastIndex` if this regex is defined globally // regex.lastIndex = 0; let m; if ((m = regex.exec(str)) !== null) { // The result can be accessed through the `m`-variable. m.forEach((match, groupIndex) => { console.log(`Found match, group ${groupIndex}: ${match}`); }); }

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 JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions