Normalize the Sort Key Before a Line Sorter Puts Item 10 Before Item 2

A pasted checklist sorts Item 1, Item 10, Item 2. The tool is comparing characters from left to right, so the zero in 10 is considered before the end of 2. The surprising order is valid lexicographic sorting, not a broken list.

Decide what each line is being sorted by

• Whole-line text works for ordinary alphabetical lists.
• Case-insensitive text avoids splitting capitalized and lowercase variants.
• Numeric values should be parsed as numbers rather than compared as strings.
• Dates are safest when normalized to YYYY-MM-DD before text sorting.
• A prefixed sequence such as 001, 002, 010 creates a sortable text key.

A dependable cleanup sequence

• Preserve a copy of the original list when order carries meaning.
• Trim accidental leading and trailing spaces.
• Normalize the part that should control order: case, number padding, or date format.
• Sort ascending or descending with Line Sorter.
• Remove duplicates only after deciding whether case and whitespace differences represent the same item.

Duplicate removal is a data rule

Alpha and alpha may be duplicates for a mailing tag list but distinct identifiers in a case-sensitive system. Sorting makes near-duplicates easier to inspect; it should not silently decide equivalence for you.