Regular Expressions 101

Save & Manage Regex

  • Current Version: 1
  • Save & Share
  • Community Library

Flavor

  • PCRE2 (PHP)
  • ECMAScript (JavaScript)
  • Python
  • Golang
  • Java
  • .NET 7.0 (C#)
  • Rust
  • PCRE (Legacy)
  • Regex Flavor Guide

Function

  • Match
  • Substitution
  • List
  • Unit Tests
Sponsors
There are currently no sponsors. Become a sponsor today!
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"^[a-z]+[0-9/\(\)G]+\s+.+\n", flags=re.MULTILINE | re.IGNORECASE) 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 = 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