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

import re regex = re.compile(r".*ad.srccountry=(?<cs1>.*?)\s.*$") test_str = "0|Fortinet|FortiGate-600E|3.2.1,build1204 (DA)|1239233|app-ctrl utm pass|4|start=Mar 06 2022 23:10:08 logver=232123123 deviceExternalId=FGBHAAAAAA1 dvchost=production01 ad.vd=prod01 ad.eventtime=1646604609212138288 ad.tz=+0100 ad.logid=0000000013 cat=traffic ad.subtype=forward deviceSeverity=notice src=10.0.0.2 spt=37628 deviceInboundInterface=Dev LAN ad.srcintfrole=lan dst=70.70.70.2 dpt=443 deviceOutboundInterface=VL-Develop1 ad.dstintfrole=undefined ad.srccountry=Norway ad.dstcountry=Denmark externalID=10999383 proto=6 act=close ad.policyid=67 ad.policytype=policy ad.poluuid=dca6b9de-adc11-51e2-d100-3cc871c8edae ad.policyname=prod01 to Internet app=HTTPS ad.trandisp=noop ad.duration=1 out=1446 in=4377 ad.sentpkt=11 ad.rcvdpkt=12 ad.shapingpolicyid=1 ad.shapersentname=Production-01 ad.shaperdropsentbyte=0 ad.shaperrcvdname=Filter-WAN ad.shaperdroprcvdbyte=0 ad.appcat=unscanned ad.mastersrcmac=a1:a1:a1:a1:a1:a1 ad.srcmac=a1:a1:a1:a1:a1:a1 ad.srcserver=0 tz=\"+0100\"" match = regex.search(test_str) if match: print(f"Match 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