My replacement inserted a literal $1.

The group does not exist in the pattern, so there was nothing to substitute. Check the group numbering — only capturing parentheses count, not (?:...) groups.

Regex Replacer

Apply a find-and-replace with capture group references.

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About this tool

Applies a pattern and a replacement across your text, showing the result and the number of substitutions. Capture groups are available in the replacement as $1, $2, $& for the whole match, and $<name> for named groups.

Questions

My replacement inserted a literal $1.: The group does not exist in the pattern, so there was nothing to substitute. Check the group numbering — only capturing parentheses count, not (?:...) groups.

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