Regular Expressions 101

(?s)applies the following effective flags to the remainder of the pattern: gs

s modifier: single line. Allows a dot to match line terminators

the literal text (case sensitive)

Non-Capturing Group(?:(?!</?p>).)*

*repeats the group contents below any number of times:

Negative Lookahead(?!</?p>)

<the literal < (60₁₀ / 74₈ / 3C₁₆)

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

p>the literal text p> (case sensitive)

.any character

the literal text (case sensitive)

Positive Lookahead(?=(?:(?!</?p>).|(?:(?!</?p>).)*)*?)

Non-Capturing Group(?:(?!</?p>).|(?:(?!</?p>).)*)*?

*?repeats the group contents below any number of times:

1st Alternative(?!</?p>).

Negative Lookahead(?!</?p>)

<the literal < (60₁₀ / 74₈ / 3C₁₆)

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

p>the literal text p> (case sensitive)

.any character

2nd Alternative(?:(?!</?p>).)*

the literal text (case sensitive)

Non-Capturing Group(?:(?!</?p>).)*

*repeats the group contents below any number of times:

Negative Lookahead(?!</?p>)

<the literal < (60₁₀ / 74₈ / 3C₁₆)

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

p>the literal text p> (case sensitive)

.any character

the literal text (case sensitive)

Global pattern flags

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

s modifier: single line. Allows a dot to match line terminators

Detailed match information will be displayed here automatically.

Search reference

Regular Expression

(?s)<p>(?:(?!</?p>).)*</p>(?=(?:(?!</?p>).|<p>(?:(?!</?p>).)*</p>)*?</p>)

New

<p><span>test12312312312312313131</span></p>

<p><span>test12</span></p>

<p>Some text
  <p><span>test1</span></p> test123 
  <p><span>test2</span></p>
  <p><span>test3</span></p>
</p>

<p><span>test12312312312312313131</span></p> <p><span>test12</span></p>  <p>Some text<p><span>test</span></p></p>