Clean Data Clean messy data in the active sheet or a specified range. Environment - If running inside Excel (Office Add-in / Office JS): Use Office JS directly ( ). Read via , write helper-column formulas via . The in-place vs helper-column decision still applies. - If operating on a standalone .xlsx file: Use Python/openpyxl. Workflow Step 1: Scope - If a range is given (e.g. ), use it - Otherwise use the full used range of the active sheet - Profile each column: detect its dominant type (text / number / date) and identify outliers Step 2: Detect issues | Issue | What to look for | |---|---|…