Using AI inside Excel, Google Sheets, Outlook, Word and PowerPoint.
Auditing a workbook is read-only, which makes it the safest use of AI in Excel. Map structure first, then hunt the four hazards that fail silently: hardcoded values, dead links, hidden sheets and stale ranges.
A column called Amount usually includes refunds as negatives. AI assumes it means revenue received, produces arithmetically perfect output describing something else, and nothing flags the difference.
A cleanup applied to five thousand rows in one pass is also a mistake applied to five thousand rows in one pass. Which cleanups you can undo, which destroy the original, and the workflow that keeps everything recoverable.
Generating the formula is the easy part. A range that starts one row too low produces a plausible wrong number that nobody notices for a quarter. Here is how to ask well, and the four-minute check that catches it.
Microsoft’s documentation states the Excel COPILOT function stops being available on 14 September 2026, and the web rollout was cancelled. If you built anything on it, this is a deadline rather than a heads-up.
Most people who pay for Copilot in Excel cannot use it on the first attempt, and it is rarely a licensing fault. Microsoft documents several conditions that must be true first, and none appear on the purchase page.
Microsoft sells AI as an add-on with a conditional price. Google bundles it and caps how often you can use it. Here is what each actually costs, what the limits are, and why Copilot in Excel sometimes does nothing at all.