Advanced Excel Masterclass in Hindi Step by step · Lab 17

Copilot in Excel: Prompts You Can Verify, Not Just Trust

Use AI to write and debug Excel formulas faster, then prove every result: test known cases, reconcile another way, keep confidential data out.

8 November 2026 · 4 min read

Broken SUMIFS returning #VALUE! and the fixed formula returning a reconciled total — Watch the lesson: Lab 17: AI-Assisted Excel - Copilot Prompts You Can Verify | Advanced Excel in Hindi

The video for this lab is in Hindi; the formulas on screen are standard Excel.

AI can write an Excel formula in seconds. It can also write a wrong one that looks perfectly reasonable. Lab 17 uses AI to speed up, and then verifies everything.

Step 1: Prompt with the facts

Tell the AI exactly what exists: the table name and its columns.

Prompt: tblOrders has columns SalesRep, OrderDate, Revenue, Status; write a formula for the month with the highest shipped revenue in 2025 — A precise prompt, then a plan to test it on three reps checked by hand.

Step 2: Test the AI’s formula independently

For each rep, the AI’s “best month” is compared with an independent calculation: a grid of SUMIFS by month for shipped 2025 revenue. If the highest month in the grid matches the AI’s answer for three reps, the formula has passed a real test.

AI best month per rep next to a SUMIFS grid of shipped revenue by month — Verify against a method you trust.

Knowledge check: an AI gives you a SUMIFS formula; what is the best first check? — The best first check: compare with a PivotTable or a total you already know.

Step 3: Debug a broken formula, and reconcile

A deliberately broken formula returns #VALUE!:

=SUMIFS(tblOrders[Revenue],tblOrders[Region],"West",Orders!C2:C500,"Shipped")

The real cause: the criteria range is a different size from the sum range, and points to the wrong column. The fix uses tblOrders[Status]. Then reconcile the fixed result with a total you already know.

Broken SUMIFS formula returning #VALUE! — Mismatched ranges: #VALUE!.

Fixed SUMIFS formula using structured references returning a total — Fixed with structured references, then reconciled.

Step 4: Data responsibility

Data responsibility: HR salaries never into a public AI tool; company-approved tools keep data in your tenant — What may go into which AI tool.

HR salaries and employee IDs never go into a public AI tool. Company-approved tools, such as Copilot with a work account, keep data in your tenant. When in doubt, share an anonymised sample instead.

A validation checklist for every AI formula

Tested on known cases?
Tested on edge cases: blank, zero, missing ID?
Reconciled to an independent method?
Uses functions available in your audience’s Excel version?

Do it yourself

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