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"
"
gmi

Test String

Code Generator

Language

Generated Code

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r"^[a-z]+[0-9/\(\)G]+\s+.+\n" test_str = ("E1 0/2/14 down down \n" "E1 0/2/15 down down \n" "GE0/0/0 down down \n" "GE0/3/0(10G) up up Conexao ao Anel AGG RMAGSRM-STRM06-01 GigabitEthernet0/4/0\n" "GE0/3/1(10G) down down \n" "GE0/4/0(10G) up up Conexao ao Anel AGG RMCOSRM0101 GigabitEthernet0/3/0\n" "GE0/4/1(10G) down down \n" "GE0/7/0 up up Conexao ao Anel ACC RMACSRM-STRM10-01 GigabitEthernet0/3/2\n" "GE0/7/1 down down \n" "GE0/7/2 down down \n" "GE0/7/3 down down \n" "GE0/7/4 down down \n" "GE0/7/5 down down \n" "GE0/7/6 down down \n" "GE0/7/7 down down \n" "GE0/8/0 up up Conexao ao Anel ACC RMACSRM-STRM04-01 GigabitEthernet0/3/3\n" "GE0/8/1 down down \n" "GE0/8/2 down down \n" "GE0/8/3 down down \n" "GE0/8/4 down down \n" "GE0/8/5 down down \n" "GE0/8/6 up down \n" "GE0/8/6.6 up up Conexao ao Servico 3G-<SRMSRMCPL113657>-<PA1808>\n" "GE0/8/7 down down \n" "Loop0 up up(s) Loopback Gerencia \n" "Loop2147483647 up up(s) DCN loopback interface \n" "NULL0 up up(s) \n" "S0/2/0:0 up up \n" "S0/5/0/1:1 down down \n" "S0/5/0/17:1 down down \n" "S0/5/0/33:1 down down \n" "S0/5/0/49:1 down down \n" "Mg0/RSP0/CPU0/1 admin-down admin-down \n" "Te0/2/0/0 up up Conexao ao RMCORJO0102 GE5/0/0\n" "Te0/2/0/1 up up Conexao ao RTOCRJO0101 [Te0/1/0/6]\n" "Te0/2/0/2 up up Conexao RMCORJO0101 Te0/0/0/2 \n" "Te0/2/0/3 up up Conexao ao LTE-TIM - PTN -ANEL01\n" "Te0/2/0/3.2001 up up CONEXAO ^`eNB\n" "Te0/2/0/3.2002 up up CONEXAO - eNB\n" "Te0/2/0/3.2003 up up Conexao ao - eNB\n" "Te0/2/0/3.2004 up up Conexao ao - eNB\n" "Te0/2/0/3.2005 up up Conexao ao - eNB\n" "Te0/2/0/3.2006 up up Conexao ao - eNB\n" "Gi0/3/1/5 up up \"Conexao ao RTISRJO0301 [Gig0/0/0] \"\n" "Gi0/3/1/6 up up Conexao ao IPX COMFONE - IPX SERVICES - CPE LOCAL - 120 Mbps\n" "Gi0/3/1/6.201 up up Conexao ao IPX COMFONE - SIGNALING/DIAMETER - 1 Mbps\n" "Gi0/3/1/6.202 up up Conexao ao IPX COMFONE - SIGNALING/SS7 - 2 Mbps\n" "Gi0/3/1/6.203 up up Conexao ao IPX COMFONE - 2/3/4G ROAMING/GRX - 60 Mbps\n" "Gi0/3/1/7 up up Conexao ao OI - Link LAB TIM/OI - ID OI RJOSL8320483\n" "Gi0/3/1/7.4000 up up RAN Sharing LTE OI - TIM [1000Mbps]\n" "Gi0/3/1/8 up up \"Conexao ao SMS CLARO\"\n" "Gi0/3/1/8.252 up up PEERING Conexao ao SMS CLARO - Trail RJORJOCPL062543 Accid 57807\n" "Gi0/3/1/9 admin-down admin-down \n" "Gi0/3/1/10 admin-down admin-down\n" " ") matches = re.finditer(regex, test_str, re.MULTILINE | re.IGNORECASE) 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