Regular Expressions 101

Group 1(www.|https?:\/\/(?:www.)?)?

?repeats the group contents below at most once:

1st Alternativewww.

wwwthe literal text www (case sensitive)

.any character (except for line terminators)

2nd Alternativehttps?:\/\/(?:www.)?

httpthe literal text http (case sensitive)

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

:the literal : (58₁₀ / 72₈ / 3A₁₆)

\/the literal / (47₁₀ / 57₈ / 2F₁₆)

Non-Capturing Group(?:www.)?

?repeats the group contents below at most once:

wwwthe literal text www (case sensitive)

.any character (except for line terminators)

Group 2([a-z-_0-9]*)

Character Class[a-z-_0-9]*

*matches any number of characters from the set below:

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

-the literal - (45₁₀ / 55₈ / 2D₁₆)

_the literal _ (95₁₀ / 137₈ / 5F₁₆)

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

Non-Capturing Group(?:\.)

\.the literal . (46₁₀ / 56₈ / 2E₁₆)

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

Regular Expression

(www.|https?:\/\/(?:www.)?)?([a-z-_0-9]*)(?:\.)

New

www.xakep.ru
https://swapi.co/api/planets/12/   //swapi
http://github.com/carbonfive/raygun //github
http://www.zombie-bites.com	//
https://www.cnet.com
http://google.co.jp
http://github.com/carbonfive/raygun
https://www.cnet.com
xewveqmwcz90sl64.co/
zx06u3ep-tcp8b25l.info
j4yfack7z7pui8b8j-d3-abfdvp.it/img/
z8rabv26m.com