Can I use backreferences like $1?

Yes — with Regex enabled. Capture groups in the find pattern can be inserted into the replacement with $1, $2, and so on.

Does it replace all occurrences?

Yes. The "g" (global) flag is always applied so every match in the text is replaced.

JavaScript regex syntax is strict — unbalanced parentheses or invalid escapes throw. The exact message is shown below the inputs to help you fix it.

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Find and replace inside a body of text. Supports regular expressions, capture groups, and case-insensitive search.

Input

Find

Replace

RegexCase-insensitiveMultiline (^/$ per-line)

Output — 4 matches

The rAIN in SpAIN falls mAINly on the plAIN.