Paste or load your CSV, tick the cleaning options you want, review the before-and-after counts in the preview, then download the cleaned CSV.
Each option is separate: trimming removes leading and trailing spaces from every cell, empty-row and empty-column removal drops lines and fields that contain nothing at all, and quote normalisation rewrites the file so only fields that genuinely need quotes have them.
Files that mix Windows CRLF and Unix LF endings break naive importers and can produce phantom blank rows. The cleaner rewrites every line break consistently in whichever style you pick, so the file loads cleanly into databases, spreadsheets and scripts.
Only in the ways you ask for. Numbers, dates and text content are never reformatted or reinterpreted, so a cleaned file still contains exactly the same data — just without the whitespace, empty structure and inconsistent quoting.