ChatGPT vs Copilot vs Claude: Which One to Use When

Every week somebody in class asks me some version of the ChatGPT vs Copilot question, usually with Claude thrown in, and what they really want is for me to name a winner. I never do, because the honest answer depends entirely on what you were about to go do next.

Here is what I see in the field. People pick a tool because a coworker mentioned it, use it for a week on tasks it was never good at, decide “AI is overrated,” and go back to doing the monthly report by hand. That is not an AI problem. That is a matching problem.

So instead of a feature chart nobody reads, here are the two things I actually tell people to do. Both take about ten minutes.

ChatGPT vs Copilot: Run One Real Task Through Both

Stop reading comparisons and run your own. Pick one task you genuinely did last week — not a toy question. Toy questions are useless here, because all three tools will happily write you a limerick and you will learn nothing.

Open ChatGPT, Copilot, and Claude in three browser tabs, attach the same file to each, and paste the exact same prompt. Something like this:

Attached is our monthly sales export. Write a 150-word summary for our regional managers. Name the top three products by revenue, flag anything that dropped more than 10% compared to last month, and end with one question I should ask the sales team.

Notice what that prompt does. It names the audience, sets a length, asks for specific numbers, and requests a judgment call at the end. Vague prompts produce vague output no matter which tool you use, and a lot of the disappointment I hear about is really just a one-line prompt problem.

Then score the three answers on three things:

• Did it get the numbers right? Check the top three against the file yourself. Every one of these tools will state a wrong total with total confidence.
• Does it sound like you? Could you send it after a two-minute edit, or would you rewrite the whole thing?
• Did it actually read the file? Some plans and some locked-down work accounts will not let you upload at all, and the tool will answer from generalities instead of your data.

The gotcha: run this test on the account you will actually use at work, not your free personal login. The free tier and the paid business tier of the same product are different animals, and a Microsoft 365 tenant with Copilot restrictions will behave differently from the Copilot demo you saw on YouTube.

Match the Tool to Where Your Data Already Lives

This is the rule that settles most of these arguments, and it has nothing to do with which model is smarter.

Use Copilot when the answer is already inside Microsoft 365. Copilot can see your mail, your calendar, your Teams chats, and your files on SharePoint and OneDrive. The other two cannot, unless you paste the material in by hand. In Outlook on the web, open a long thread and use the Summary panel Copilot puts at the top of the message. In Teams, open a recorded meeting and go to Recap, then ask “What did I commit to in this meeting?” In Excel, go to the Home tab and click Copilot — but first select your data and press Ctrl+T to make it a real table. Copilot in Excel routinely refuses to work on a loose range, and that single step is the fix for most “Copilot doesn’t work for me” complaints I hear.

Use Claude when the job is a long document or a multi-step project. Upload a 60-page policy PDF and ask “List every deadline in this document, with the page number for each one.” The page numbers matter — they give you a way to verify the answer in about a minute. Claude also holds a lot of context at once, so it is the one I reach for when I am reworking a whole training manual rather than a paragraph.

Use ChatGPT when you want quick analysis of a file sitting on your desktop. Drop in a messy CSV and ask it to clean the columns, chart the trend, and hand the file back. It will write and run the code to do it.

The gotcha: anything you paste into a personal account leaves your employer’s control. Check your company’s policy before you upload a customer list to anything, and assume the answer is no until somebody in writing tells you otherwise.

Plenty More on the Calendar

If you want to see all three tools side by side on the same tasks rather than reading about it, I am running ChatGPT vs Copilot vs Claude: The Best AI Tool for Your Business live on Thursday, September 3. We run the same real business tasks through each one, look at where each falls down, and I give you a straight recommendation for the kind of work you do.

The full current schedule is on the front page of PCWebinars.com, with new dates going up as they get confirmed. Register for this one, or browse the rest and find the session that fits what is 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.

You can find the full list of upcoming live sessions, recordings, and courses at PCWebinars.com.