Regular Expressions 101

1st Alternative(?<!\S)(?:(?:https?|www)\S+|/+(?!\S))(*SKIP)(*FAIL)

Negative Lookbehind(?<!\S)

\Sany non-whitespace character

Non-Capturing Group(?:(?:https?|www)\S+|/+(?!\S))

1st Alternative(?:https?|www)\S+

Non-Capturing Group(?:https?|www)

1st Alternativehttps?

httpthe literal text http (case sensitive)

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

2nd Alternativewww

wwwthe literal text www (case sensitive)

\S+any non-whitespace character, repeated at least once

2nd Alternative/+(?!\S)

/+the literal / (47₁₀ / 57₈ / 2F₁₆) , repeated at least once

Negative Lookahead(?!\S)

\Sany non-whitespace character

(*SKIP)acts like (*PRUNE), but the next unanchored match attempt starts where (*SKIP) was reached instead of at the next subject character

(*FAIL)forces the current match attempt to fail at this position

2nd Alternative/

/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

(?<!\S)(?:(?:https?|www)\S+|/+(?!\S))(*SKIP)(*FAIL)|/

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American English/British English


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