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Text Cleanup & Line Tools

Add Prefix to Lines

Prefix list items, paths, labels, code fragments, or plain text lines while optionally skipping blank lines.

Before / afterLine endingsUTF-8 bytesRepeat safely

Text cleanup runs locally in your browser. These tools operate on plain text lines; structured CSV/JSON/XML and regex workflows remain in their dedicated tools.

Prefixing preserves line order

Skipping blank lines changes how empty and trailing lines are treated. The audit makes those boundaries visible.

Repeatable text workflow

Use output as input only when the preview is what you intended. Restore returns to the page-load sample, and the before/after audit remains local to your browser.

Practical guide and verification

Use the tool first, then apply these checks to verify inputs, interpret the result, and hand it off without displacing the primary workflow.

Verify whether blank lines should change

A literal prefix operation can intentionally touch every line or skip empty lines. Decide that rule before processing logs, lists, code, or configuration text, then compare the output line count with the source. A visually harmless extra prefix on a blank line can become meaningful in a parser or diff.

Preserve line endings when the destination cares

Browsers often normalize pasted text to line-feed characters even when the original file used Windows CRLF or another convention. If the result will return to a repository, shell script, batch file, or strict import process, verify the saved line-ending format separately instead of assuming the visible text area preserved it.

Treat the prefix as literal data

This tool adds the entered prefix; it is not a regular-expression replacement or syntax-aware formatter. Characters such as quotes, slashes, comment markers, commas, or tabs may have special meaning in the destination format. Test a small sample and inspect the first, middle, and final lines before applying the result broadly.

Use a round-trip check for structured lists

When prefixes are being added to create bullets, comments, paths, SQL fragments, or identifiers, remove the prefix from a copy and verify that the original line payloads return unchanged. This catches accidental trimming, blank-line changes, or pasted characters that are hard to notice in a long result.

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