# Get Excel totals you can trust after Copilot cleans your data

> It explains each hidden problem and why it would throw off a formula, then lets you pick which fixes go in.

Ask Copilot in Excel to check your sheet for hidden problems like extra spaces, mixed date formats, duplicates and numbers stored as text, then pick which fixes to apply before you total anything.

- Page: https://thesolocreators.com/prompts/excel-copilot-clean-data-before-totals/
- Category: Hidden AI superpowers
- Made for: Small business owners, Consultants, Coaches
- Works in: Copilot
- Time: About 5 minutes
- Effort: A few steps
- Note: Needs Copilot in Excel. The clean data skill is rolling out on Excel for Windows, Mac and web as of 2026-10-27.
- Published: 2026-10-29

## Why are my Excel totals wrong and how do I fix them?

Run the clean data skill in Copilot in Excel by typing @clean-data or picking it from the Skills menu. It finds issues like extra spaces, mixed dates, duplicates and numbers stored as text, then proposes fixes you choose. As of October 2026, it's rolling out on Excel for Windows, Mac and the web. If you have one small list, a single check is enough. If you build reports from the sheet, run it before every PivotTable.

## The prompt

Fill in the parts in [square brackets], or leave them and the AI will ask you for them.

```text
@clean-data Check the [SHEET NAME, e.g. 2026 Invoices] sheet before I build totals and a PivotTable from it. Look for anything that would make sums, lookups or counts wrong: extra spaces, names spelled two ways, dates in mixed formats, duplicate rows and numbers stored as text. The columns I care about most are [KEY COLUMNS, e.g. Client, Date, Amount]. Treat [WHAT COUNTS AS DUPLICATE, e.g. same client, date and amount] as a duplicate. For each problem, tell me in plain words how many rows it affects and what it would have thrown off. Propose fixes, but don't apply anything until I choose.
```

## Step by step

1. Open the workbook with your sales, client or invoice list in Excel
2. Open Copilot and type @clean-data, or pick it from the Skills menu
3. Paste the prompt and name the sheet and columns that matter
4. Review the proposed fixes and apply only the ones you agree with

## What you'll get

A plain-words list of the hidden problems in your sheet, how many rows each affects, and proposed fixes you approve one by one.

## Good to know

**Why are my Excel totals wrong and how do I fix them?** Run the clean data skill in Copilot in Excel by typing @clean-data or picking it from the Skills menu. It finds issues like extra spaces, mixed dates, duplicates and numbers stored as text, then proposes fixes you choose. As of October 2026, it's rolling out on Excel for Windows, Mac and the web. If you have one small list, a single check is enough. If you build reports from the sheet, run it before every PivotTable.

**Which AI tools does this work in?** It works in Copilot. On this page, one tap copies the prompt and opens the app, so you just paste. Needs Copilot in Excel. The clean data skill is rolling out on Excel for Windows, Mac and web as of 2026-10-27.

**How long does it take?** About 5 minutes. It's rated "A few steps". There are 4 steps, listed above.

**What do I need before I start?** Just your details for 3 blanks: sheet name, key columns and what counts as duplicate. You can skip any, and your AI will ask for them.

**What will I get back?** A plain-words list of the hidden problems in your sheet, how many rows each affects, and proposed fixes you approve one by one.

Idea spotted on the official docs, shared by Microsoft Excel team: https://techcommunity.microsoft.com/blog/excelblog/whats-new-in-excel-october-2026/4549758. The prompt is The Solo Creators' own version.

## Go further

Ready-made skills in the Solo Creators AI Studio (https://thesolocreators.com/studio/) that fit this: No AI Slop (A sharp editor that cuts the AI tells from any draft. Your point and your voice stay); TLDR (Your AI stops writing walls of text: every reply leads with the next action, numbered and skimmable).

From AI Use Cases and Prompts by The Solo Creators: https://thesolocreators.com/prompts/. Free to use; please link back to the page when you share it.