Regular Expressions 101

Explanation

Pro

^start of line

Negative Lookahead(?!(?:.*?{{REPLACE}}){2})

Non-Capturing Group(?:.*?{{REPLACE}}){2}

{2}repeats the group contents below exactly 2 times:

.*?any character (except for line terminators), repeated any number of times

{{REPLACE}}the literal text {{REPLACE}} (case sensitive)

.*?any character (except for line terminators), repeated any number of times

{{REPLACE}}the literal text {{REPLACE}} (case sensitive)

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

Match Information

Detailed match information will be displayed here automatically.

Quick Reference

26 tokens

Regular Expression

^(?!(?:.*?{{REPLACE}}){2}).*?{{REPLACE}}

New

{{REPLACE}}. // Valid
{{REPLACE}} {{REPLACE}}. // Invalid
{{REPLACE}}{{REPLACE}}. // Invalid
Text here {{REPLACE}}. More text here. // Valid
{{REPLACE}} text here {{REPLACE}}. More text here // Invalid