Regular Expressions 101

\ban ASCII word boundary

Non-Capturing Group(?: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 text ://

Non-Capturing Group(?:(?i:[a-z]+\.)+)

Group with flags gi(?i:[a-z]+\.)+

+repeats the group contents below at least once:

i modifier: insensitive. Matches without distinguishing uppercase and lowercase letters

Character Class[a-z]+

+matches at least one character from the set below:

a-zone character from a (97₁₀) to z (122₁₀) (case insensitive)

\.the literal . (46₁₀ / 56₈ / 2E₁₆)

Negated Character Class[^\s,]+

+matches at least one character outside the set below:

\sany whitespace character

,the literal , (44₁₀ / 54₈ / 2C₁₆)

\ban ASCII word boundary

Global pattern flags

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

Detailed match information will be displayed here automatically.

Search reference

Regular Expression

\b(?:https?://)?(?:(?i:[a-z]+\.)+)[^\s,]+\b

New

This is just a post to test regex for extracting URL http://google.com, https://www.youtube.com/watch?v=dlw32af https://instagram.com/oscar/ en.wikipedia.org
Even works for www.wikipedia.de, https://de.wikipedia.org/wiki/Wikipedia:Hauptseite or any other https://en.wikipedia.org/wiki/Regular_expression url. Even comma separated www.url1.com,www.url2.com

Regular Expression

Substitution