Regular Expressions 101

Save & Share

  • Regex Version: ver. 1
  • Update Regex
    ctrl+⇧+s
  • Save new Regex
    ctrl+s
  • Add to Community Library

Flavor

  • PCRE2 (PHP >=7.3)
  • PCRE (PHP <7.3)
  • ECMAScript (JavaScript)
  • Python
  • Golang
  • Java 8
  • .NET 7.0 (C#)
  • Rust
  • Regex Flavor Guide

Function

  • Match
  • Substitution
  • List
  • Unit Tests

Tools

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
No Match

~
~
gm

Test String

Substitution

Processing...

Code Generator

Language

Generated Code

re = /^(\d{1,3}(?:\.\d{1,3}){3})\s*-\s*((?1))\s*-\s*((?:[0-9A-Fa-f]{2}[:-]){3,6}[0-9A-Fa-f]{2})\s*-\s*(\d\d\/\d\d\/\d{4}\s\d\d(?::\d\d){2}|NEVER EXPIRES|INACTIVE)\s*-\s*(\w)\s*-\s*(.*)$/m str = 'Changed the current scope context to 192.25.200.0 scope. Type : N - NONE, D - DHCP B - BOOTP, U - UNSPECIFIED, R - RESERVATION IP ============================================================================================ IP Address - Subnet Mask - Unique ID - Lease Expires -Type -Name ============================================================================================ 192.25.200.4 - 255.255.255.192- 64-9e-f3-b3-81-d3 -01/08/2018 17:07:46 -D- BH1-WAP-01.local 192.25.200.5 - 255.255.255.192- 50-57-a8-30-11-f6 -01/08/2018 16:24:59 -D- BH1-WAP-03.local 192.25.200.6 - 255.255.255.192- f0-f7-55-df-c4-ff -01/08/2018 16:45:04 -D- BH1-WAP-02.local 192.25.200.7 - 255.255.255.192- 00-23-24-bb-ce-83 -04/08/2018 10:55:00 -D- CESTA1703043.LOCAL No of Clients(version 4): 4 in the Scope : 192.25.200.0. Command completed successfully. Changed the current scope context to 192.25.200.64 scope. Type : N - NONE, D - DHCP B - BOOTP, U - UNSPECIFIED, R - RESERVATION IP ============================================================================================ IP Address - Subnet Mask - Unique ID - Lease Expires -Type -Name ============================================================================================ 192.25.200.68 - 255.255.255.192- 28-94-0f-05-ac-6c -01/08/2018 03:14:46 -D- WAP-C12-01-1047.local No of Clients(version 4): 1 in the Scope : 192.25.200.64. Command completed successfully. Changed the current scope context to 192.28.211.0 scope. 192.28.211.27 - 255.255.255.0 -00-0a-13-00-00-00-00- NEVER EXPIRES -U- CFCameraNearlockers Changed the current scope context to 192.28.194.0 scope. 192.28.194.254 - 255.255.255.0 -00-48-32-95-85 - INACTIVE -N- bms' subst = '$1 ~ $2 ~ $3 ~ $4 ~ $5 ~ $6' result = str.gsub(re, subst) # Print the result of the substitution puts result

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 Ruby, please visit: http://ruby-doc.org/core-2.2.0/Regexp.html