Cleaning up a messy Excel spreadsheet can easily take longer than building it in the first place. Microsoft recommends using structured tables for the best results, but I wanted to see how Copilot handled a genuinely messy workbook. But many of the most obvious formatting problems remained. If I inherited a messy workbook tomorrow, I wouldn't get Copilot to fix it. For now, though, I'd still reach for Excel's built-in cleanup tools before asking Copilot to fix another messy workbook.