Regular Expressions 101

Pro

^start of line

Group 1(.*?)

.*?any character (except for line terminators), repeated any number of times

Non-Capturing Group(?:(:)([0-9]*))?

?repeats the group contents below at most once:

Group 2(:)

:the literal : (58₁₀ / 72₈ / 3A₁₆)

Group 3([0-9]*)

Character Class[0-9]*

*matches any number of characters from the set below:

0-9one character from 0 (48₁₀) to 9 (57₁₀)

$end of line

Global pattern flags

g modifier: global. Finds all matches instead of stopping after the first

m modifier: multiline. Causes ^ and $ to match the start and end of each line, not only the start and end of the string

Detailed match information will be displayed here automatically.

25 tokens

^(.*?)(?:(:)([0-9]*))?$

New

[ab:cd::0]:22
host.domain.com:443
1.2.3.4:22
host.domain.com
host.domain.com:
host.domain.com:333