Regular Expressions 101

Save & Manage Regex

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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

import re regex = re.compile(r"CEF:0.+[\r\n]?", flags=re.MULTILINE) test_str = ("CEF:0|Forcepoint CASB|Cloud Service Monitoring|1.0|63575192763|Activity|0|act=Monitor app= cat=Normal Activity cs1= destinationServiceName=Office365 deviceExternalId= deviceFacility=true deviceProcessName=loadBalancers dhost= dpriv=User dst=0.0.0.0 duser=14dd43c6-a792-4c07-a33b-c5e561a129de dvc=10.1.2.12 dvchost=somedomain end=1600408516000 externalId=0 fsize=-1 msg=//United States/Unknown outcome=Success proto= reason=modify request= requestClientApplication=Unknown/Unknown/\"\" rt=1600408516000 sourceServiceName=Unmanaged src=someIP start=1600408516000 suser= cs2= cs3= cs5=false cs6= dproc=Unknown flexString1=mc_rg-int-qa-eus02_aks-int01-qa-eus02_eastus2,kubernetes-internal cs4=14dd43c6-a792-4c07-a33b-c5e561a129de flexString2= AD.ThreatRadarCategory= AD.TORNetworks= AD.MaliciousIPs= AD.AnonymousProxies= AD.IPChain=someIP AD.IPOrigin=External AD.samAccountName=14dd43c6-a792-4c07-a33b-c5e561a129de\n" "CEF:0|Forcepoint CASB|Cloud Service Monitoring|1.0|63575216734|Activity|0|act=Monitor app= cat=Normal Activity cs1= destinationServiceName=Office365 deviceExternalId= deviceFacility=false deviceProcessName= dhost= dpriv=User dst=0.0.0.0 duser=someuser_849fcb2777e9@somedomain.onmicrosoft.com dvc=10.1.2.12 dvchost=somedomain end=1600406172000 externalId=0 fsize=-1 msg=//United States/Unknown outcome=Success proto= reason=login request= requestClientApplication=Unknown/Unknown/\"\" rt=1600406172000 sourceServiceName=Unmanaged src=someIP start=1600406172000 suser= cs2= cs3= cs5=false cs6= dproc=Unknown flexString1= cs4=someaccount9@somedomain.onmicrosoft.com flexString2= AD.ThreatRadarCategory= AD.TORNetworks= AD.MaliciousIPs= AD.AnonymousProxies= AD.IPChain=someIP AD.IPOrigin=Internal AD.samAccountName=someaccount9@somedomain.onmicrosoft.com\n" "CEF:0|Forcepoint CASB|Cloud Service Monitoring|1.0|63575216736|Activity|0|act=Monitor app= cat=Normal Activity cs1= destinationServiceName=Office365 deviceExternalId= deviceFacility=true deviceProcessName= dhost= dpriv=User dst=0.0.0.0 duser=someaccount@somedomain.onmicrosoft.com dvc=10.1.2.12 dvchost=somedomain end=1600405713000 externalId=0 fsize=-1 msg=//United States/Unknown outcome=Success proto= reason=login request= requestClientApplication=Unknown/Unknown/\"\" rt=1600405713000 sourceServiceName=Unmanaged src=someIP start=1600405713000 suser= cs2= cs3= cs5=false cs6= dproc=Unknown flexString1= cs4=someaccount@somedomain.onmicrosoft.com flexString2= AD.ThreatRadarCategory= AD.TORNetworks= AD.MaliciousIPs= AD.AnonymousProxies= AD.IPChain=someIP AD.IPOrigin=External AD.samAccountName=someaccount@somedomain.onmicrosoft.com\n" "CEF:0|Forcepoint CASB|Cloud Service Monitoring|1.0|63575216738|Activity|0|act=Monitor app= cat=Normal Activity cs1= destinationServiceName=Office365 deviceExternalId= deviceFacility=false deviceProcessName= dhost= dpriv=User dst=0.0.0.0 duser=someaccount@somedomain.com dvc=10.1.2.12 dvchost=somedomain end=1600405674000 externalId=0 fsize=-1 msg=/1225/United States/Unknown outcome=Success proto= reason=login request= requestClientApplication=Unknown/Unknown/\"\" rt=1600405674000 sourceServiceName=Unmanaged src=someIP start=1600405674000 suser= cs2= cs3= cs5=false cs6= dproc=Unknown flexString1= cs4=someaccount flexString2= AD.ThreatRadarCategory= AD.TORNetworks= AD.MaliciousIPs= AD.AnonymousProxies= AD.IPChain=someIP AD.IPOrigin=Internal AD.samAccountName=someaccount\n" "CEF:0|Forcepoint CASB|Cloud Service Monitoring|1.0|63575216735|Activity|0|act=Monitor app= cat=Normal Activity cs1= destinationServiceName=Office365 deviceExternalId= deviceFacility=false deviceProcessName= dhost= dpriv=User dst=0.0.0.0 duser=someaccount9@somedomain.onmicrosoft.com dvc=10.1.2.12 dvchost=somedomain end=1600406165000 externalId=0 fsize=-1 msg=//United States/Unknown outcome=Success proto= reason=login request= requestClientApplication=Unknown/Unknown/\"\" rt=1600406165000 sourceServiceName=Unmanaged src=someIP start=1600406165000 suser= cs2= cs3= cs5=false cs6= dproc=Unknown flexString1= cs4=someaccount@somedomain.onmicrosoft.com flexString2= AD.ThreatRadarCategory= AD.TORNetworks= AD.MaliciousIPs= AD.AnonymousProxies= AD.IPChain=someIP AD.IPOrigin=Internal AD.samAccountName=someaccount@somedomain.onmicrosoft.com") matches = regex.finditer(test_str) for match_num, match in enumerate(matches, start=1): print(f"Match {match_num} was found at {match.start()}-{match.end()}: {match.group()}") for group_num, group in enumerate(match.groups(), start=1): print(f"Group {group_num} found at {match.start(group_num)}-{match.end(group_num)}: {group}")

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