Does it support lookahead/lookbehind?

Yes. Positive/negative lookahead (?=, ?!) and lookbehind (?<=, ?<!) are fully supported in modern browsers.

Regex Find & Replace - Search Replace with Regex

Find and replace text using regular expressions. Test patterns, use capture groups, preview changes. Free, private, works offline.

Find (Regex Pattern)

Replace With

Global (g)

Case insensitive (i)

Multiline (m)

Dotall (s)

Input Text

0 matches found

Match Preview

Matches will be highlighted here

Result Preview

Replacement result will appear here

Output Text

Common Patterns Reference

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Use parentheses to capture: (\w+). Reference in replacement with $1, $2, etc. Example: swap words with (\w+) (\w+) → $2 $1

Global (g), case-insensitive (i), multiline (m), dotall (s), and unicode (u). Enable them with checkboxes.

Yes. The preview shows matches highlighted and the result after replacement. Apply only when satisfied.

Yes. All processing happens in your browser using JavaScript. No data is sent to any server.

Global (g) replaces all matches. Without it, only the first match is replaced. Almost always use global for find/replace.

Yes. Use $& for full match, $` for text before match, $' for text after, and $1-$99 for capture groups.

Use backslash to escape regex special characters: \., \*, \?, \+, \[, \], $, $, \{, \}, \|, \^, \$, \\.

Yes. Enable the case-insensitive (i) flag to match regardless of case, then use replacements as needed.

Yes. Positive/negative lookahead (?=, ?!) and lookbehind (?<=, ?

Yes. Perfect for batch renaming patterns, reformatting data, cleaning up text files, and data transformation tasks.