Regular Expressions 101

^start of line

Non-Capturing Group(?:https?:\/\/)?

?repeats the group contents below at most once:

httpthe literal text http (case insensitive)

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

: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 insensitive)

\.the literal . (46₁₀ / 56₈ / 2E₁₆)

examplethe literal text example (case insensitive)

\.the literal . (46₁₀ / 56₈ / 2E₁₆)

Character Class[a-zA-Z0-9./]+

+matches at least one character from the set below:

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

A-Zone character from A (65₁₀) to Z (90₁₀) (case insensitive)

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

.the literal . (46₁₀ / 56₈ / 2E₁₆)

/the literal / (47₁₀ / 57₈ / 2F₁₆)

$end of line

Global pattern flags

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

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

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?:\/\/)?(?:www\.)?example\.[a-zA-Z0-9./]+$

New

example.com
www.example.com
http://example.com
https://www.example.com
example.com/exam1/exam.php
example.com/exam