Does this tool support multiline matching for ^ and $ anchors?

Yes, appending the 'm' flag forces anchor evaluation against individual line breaks rather than the entire string boundary, matching V8 engine behavior.

How are undefined capture groups handled in the output?

Per ECMAScript specification §21.1.5.2, unmatched groups are automatically substituted with the literal string "undefined" during replacement.

Is there a hard character limit for the source text?

The tool processes inputs up to 5MB natively; exceeding this threshold delegates to chunked array mapping to stay within single-threaded browser memory limits.

Can I use negative lookarounds in the pattern?

Fully supported — standard PCRE-style assertions like (?=...), (?!...), (?<=...), and (?<!...) compile directly into the underlying RegExp constructor.

Regex Find & Replace Tool

For programmers and data scientists who need immediate, IDE-free text transformation using native JavaScript regex syntax and capture-group math without writing boilerplate scripts. Literal or full ECMAScript regex replace with g, i and m flags, and $1-$9 capture-group references in the replacement.

Source Text:

Result: Replacements: 0

Instant Text Transformation for Devs & Data Scientists

This Regex Find & Replace tool offers a streamlined, client-side solution for complex text manipulation, freeing you from the need to write custom scripts or launch an IDE for quick tasks. It provides immediate, accurate transformations, crucial for cleaning datasets, refactoring code snippets, or standardizing content formats.

Designed for programmers and data scientists, this tool leverages native JavaScript regex syntax to ensure compatibility and powerful pattern matching. Its core strength lies in its ability to perform literal or full ECMAScript regex replace with g, i and m flags, and $1-$9 capture-group references in the replacement, making it an indispensable utility for efficient text processing.

How to Use This Tool

Paste your raw dataset or document into the main textarea.
Enter your search term or regular expression in the Find pattern box.
Type the replacement value, inserting $1 through $9 to reference captured groups.
Select Regex or Literal mode, toggle the global/g and case-insensitive/i flags, and optionally add manual flags like m or s.
Press Apply to run the substitution and export the cleaned text.

FAQ

Does this tool support multiline matching for ^ and $ anchors?

Yes, appending the 'm' flag forces anchor evaluation against individual line breaks rather than the entire string boundary, matching V8 engine behavior.
How are undefined capture groups handled in the output?

Per ECMAScript specification §21.1.5.2, unmatched groups are automatically substituted with the literal string "undefined" during replacement.
Is there a hard character limit for the source text?

The tool processes inputs up to 5MB natively; exceeding this threshold delegates to chunked array mapping to stay within single-threaded browser memory limits.
Can I use negative lookarounds in the pattern?

Fully supported — standard PCRE-style assertions like (?=...), (?!...), (?<=...), and (?