How to Ask Copilot to Explain an Excel Formula Step by Step

You have a complex Excel formula in a cell, and you need to understand what each part does. Manually tracing nested functions and cell references is time-consuming and error-prone. Copilot in Excel can read the formula and break it down into plain English, one function at a time. This article shows you exactly how to request a step-by-step explanation and what to do if the output is incomplete.

How Copilot Reads and Explains an Excel Formula

Copilot uses the Microsoft Graph and the Excel calculation engine to parse the formula in the selected cell. It does not evaluate the formula; it reads the syntax and translates each function and argument into natural language. The explanation covers the purpose of each function, the role of each argument, and how the parts combine to produce the final result.

Before you start, ensure you have the following:

• A Microsoft 365 subscription that includes Copilot for Microsoft 365. Copilot in Excel is not available in Copilot Pro.
• Excel for Windows version 2402 or later, or Excel for the web with the Copilot toggle enabled.
• A worksheet that contains at least one formula. The formula can be simple, like =SUM(A1:A10), or nested, like =IF(VLOOKUP(B2,Sheet2!A:B,2,FALSE)>100,”High”,”Low”).
• Your file saved to OneDrive or SharePoint. Copilot cannot read formulas in local-only files.

The explanation appears in the Copilot pane as text. You can copy it, ask for more detail on a specific part, or request a rewritten version of the formula in simpler terms.

Steps to Get a Step-by-Step Formula Explanation

Follow these steps to have Copilot explain any formula in your workbook.

1. Open the Copilot pane
   In Excel, go to the Home tab and click Copilot in the ribbon. The Copilot pane opens on the right side of the window. If you do not see the Copilot button, your admin may have disabled it or your license may not include Copilot for Microsoft 365.
2. Select the cell containing the formula
   Click the cell that has the formula you want explained. Copilot reads the formula from the active cell only. If you select a range, Copilot uses the top-left cell of the range. Verify that the formula bar shows the correct formula before proceeding.
3. Type your request in the prompt box
   In the Copilot pane prompt box, type “Explain this formula step by step” and press Enter. Do not add extra words like “please” or “can you” — the shorter prompt works best. Copilot processes the formula and displays the explanation in the pane.
4. Review the explanation
   Copilot lists each function in the order it executes. For a nested formula, it starts with the innermost function and works outward. Each line shows the function name, its arguments, and what the function returns. If the explanation is too long, scroll down in the pane.
5. Ask a follow-up question if needed
   If a specific function is still unclear, type a question such as “Tell me more about the VLOOKUP part” or “What does the FALSE argument do in VLOOKUP?” Copilot responds with a focused explanation of that function only.

If you want the explanation in a different style, try prompts like “Explain this formula in plain English” or “Break this formula into simple steps”. Copilot adjusts the tone and detail level based on your wording.

Common Issues When Asking Copilot to Explain a Formula

Copilot says “I cannot find a formula in the selected cell”

This error occurs when the active cell contains a value or text instead of a formula, or when the cell is empty. To verify, look at the formula bar. If it shows a number or text, the cell does not contain a formula. Select the correct cell or check that the cell is not formatted as text. If the cell contains a formula but Copilot still cannot read it, save the file to OneDrive or SharePoint first.

Copilot explains only part of the formula

Copilot may truncate the explanation for very long formulas containing more than 10 nested functions or exceeding 500 characters. To get the full breakdown, split the formula into smaller parts. Create helper columns that compute intermediate results, then ask Copilot to explain each helper column separately. Alternatively, ask “Explain the first three functions of this formula” to get a partial explanation.

Copilot returns generic output instead of a step-by-step breakdown

If Copilot responds with a general description of the formula’s purpose rather than a line-by-line breakdown, your prompt may be too vague. Use the exact phrase “Explain this formula step by step”. Avoid prompts like “What does this do?” or “Help me with this formula.” The specific wording triggers the step-by-step mode.

Copilot does not appear in Excel

The Copilot button is missing from the Home tab. This usually means your Microsoft 365 license does not include Copilot for Microsoft 365, or your IT admin disabled the feature. Check your subscription in the Microsoft 365 admin center under Billing > Your products. If you have the correct license, ask your admin to enable Copilot in the Microsoft 365 admin center > Settings > Org settings > Copilot page.

Copilot Pro vs Copilot for Microsoft 365: Formula Explanation Features

Item	Copilot Pro	Copilot for Microsoft 365
Available in Excel	No	Yes
Step-by-step formula explanation	Not available	Yes, with the exact prompt shown above
Follow-up questions on formula parts	Not available	Yes
File location requirement	No Excel integration	File must be on OneDrive or SharePoint

Copilot for Microsoft 365 is the only version that can analyze formulas inside Excel. Copilot Pro works in Word, PowerPoint, and Outlook but cannot read Excel cells. If you only need formula explanations, a Copilot for Microsoft 365 license is required.

You can now ask Copilot to explain any formula in your workbook and get a plain-language breakdown of each function and argument. For nested formulas, start with the innermost function and work outward. If the explanation is incomplete, split the formula into helper columns and ask again. For deeper understanding, use follow-up prompts like “Explain the IFERROR function in more detail” to isolate a single component.