Regular Expressions 101

^start of line

Group 1(https?:)?

?repeats the group contents below at most once:

httpthe literal text http (case sensitive)

s?optionally matches the literal s (115₁₀ / 163₈ / 73₁₆) (case sensitive)

:the literal : (58₁₀ / 72₈ / 3A₁₆)

//the literal text //

Group 2([^/]*\.)?

?repeats the group contents below at most once:

Negated Character Class[^/]*

*matches any number of characters outside the set below:

/the literal / (47₁₀ / 57₈ / 2F₁₆)

\.the literal . (46₁₀ / 56₈ / 2E₁₆)

examplethe literal text example (case sensitive)

\.the literal . (46₁₀ / 56₈ / 2E₁₆)

comthe literal text com (case sensitive)

/?optionally matches the literal / (47₁₀ / 57₈ / 2F₁₆)

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.

Search reference

Regular Expression

^(https?:)?//([^/]*\.)?example\.com/?

New

With protocol:

http://example.com
https://example.com/folder/file.txt
https://www.example.com/toto
https://sub-domain.example.com
https://sub-sub.sub.example.com
https://www.google.com/?q=example.com

Without protocol:
//example.com/no-i-do-not-want-it-either
//valid.com/blablabla

Regular Expression

Extraction