ChatGPT and Copilot: Two Jobs to Split Between Them

Almost every class I teach now has the same question in it somewhere: I have ChatGPT and Copilot sitting on my desktop, so which one am I supposed to open? People pay for both, use neither well, and end up doing the work by hand anyway because deciding takes longer than just fixing the spreadsheet themselves.

The honest answer is that they are not competitors. They are two different tools that happen to talk the same way. One of them can see your files. The other one cannot, and that turns out to be the whole distinction.

Here are the two habits that sort it out, and you can build both of them this afternoon.

ChatGPT and Copilot: Let Copilot Handle Your Real Files

Copilot’s advantage is that it is already inside the file. It can read the sheet you have open, the thread you are staring at, and the document you are editing, without you copying anything anywhere.

The place this pays off fastest is Excel. Say you have an aging report and you want to flag the accounts that are getting dangerous. Do this:

• Click anywhere in your data, then go to Home → Format as Table. Copilot in Excel will not touch a plain range — it needs a real table with headers.
• Click the Copilot button on the Home tab.
• Type: Add a column called Risk Flag that says "Follow up" when Days Outstanding is over 45 and the balance is over 5000, and "OK" otherwise.

Copilot writes the formula, shows it to you, and inserts the column when you click Keep it. It took the sentence you would have said out loud and turned it into a nested IF you did not have to remember the syntax for. Change the numbers in the prompt and run it again — that is faster than editing the formula by hand.

The same idea works in Outlook. At the top of a forty-message thread there is a Summary by Copilot bar. Open it and you get the decisions and the open questions, with links back to the message each one came from, so you can check it instead of trusting it.

The gotcha: Copilot in Excel only works on a file saved to OneDrive or SharePoint with AutoSave on. If your workbook is sitting in a local Downloads folder, the Copilot button will be there and it will refuse to do anything useful. Save the file to OneDrive first — that is the fix nine times out of ten when someone tells me “Copilot doesn’t work.”

Give ChatGPT the Blank Page and the Rewrite

ChatGPT cannot see your files, and that stops being a problem the moment you stop asking it to. What it is genuinely better at is the writing and thinking work: turning a mess of notes into something a person can read, arguing with your logic, and producing five options when you are stuck on zero.

The trick is to tell it who it is writing for and what shape you want back. Compare these two:

• Weak: Write an email about the late invoices.
• Strong: You are writing as an accounts receivable manager. Write a short, friendly email to a long-standing customer who is 52 days late on one invoice. Keep it under 120 words, do not threaten anything, and end with one specific question that makes it easy for them to reply. Give me three versions: warm, neutral, and firm.

The second prompt gets you something you can send after a small edit. The first gets you a form letter. The difference is not the tool — it is that you specified the audience, the length, the tone, and the number of options.

Once you have the version you want, that is when you go back to Microsoft 365: paste it into Outlook and let Copilot check it against the thread you are replying to.

The gotcha: strip the identifying details before you paste anything into ChatGPT. Customer names, account numbers, salary figures, anything covered by a client agreement. Replace them with placeholders like [CUSTOMER] and put the real values back in Word or Outlook afterward. Copilot inside your Microsoft 365 tenant is governed by your organization’s data rules; a consumer ChatGPT account is not, and that is a distinction worth being careful about.

Plenty more on the calendar

If you want to see all of this done live rather than read about it, I am running 3-Hour Virtual Seminar on Using ChatGPT and Copilot to be More Productive in Microsoft 365 on Thursday, October 1. It is a working session across Excel, Outlook, Word, and Teams — where each tool wins, the prompt patterns that hold up, and the ones that waste your time. Bring your own messy file and you will leave with it cleaned up.

The full current schedule is on the front page of PCWebinars.com, with new dates going up as they are confirmed. Register for this one, or have a look through the others and find the session that matches what is actually on your plate this month.

About your trainer

I’m Tom Fragale. I’ve been a computer trainer and consultant for more than 30 years, and I’ve taught well over 30,000 people how to get more out of the software they already own — Excel, Access, Power BI, Word, Outlook, and now the AI tools that sit on top of all of it: Claude, ChatGPT, and Microsoft Copilot. My background is applied, not theoretical. Alongside teaching, I build real databases and reporting systems for clients in Excel, Access, and Power BI, so the examples I use in class are the problems I ran into last week, not textbook exercises. I also publish free tutorials on YouTube and longer courses online.

If any of this was useful, there is a lot more of it waiting for you at PCWebinars.com.