What to Ask Claude — and What to Keep (Plus Privacy)

What to ask Claude in Excel — and what to keep for yourself

Goal: by the end of these ~10 minutes you know which spreadsheet jobs to hand to Claude, which ones stay with you, and how to work with client data without pasting it into a chat.

Plan check: everything in this lesson works on Claude's free plan (chat, attaching a file, and Claude running a short analysis on a demo file) plus free Google Sheets or any recent Excel. The free plan has lower usage limits. The Claude for Excel add-in (works inside Excel) needs a paid Claude plan (Pro and up, about $20/month) — it is optional here.

Before you start

Download the demo folder (one click each). All names and numbers in the demo files are fictional.

• clients-personal-data-demo.csv — fictional personal data for the privacy exercise
• invoices-h1-2026.csv and clients.csv — used in lesson 2
• README.txt — what every file contains

Where Claude helps, where you stay in charge

The pattern: Claude drafts the method, you run it and check it. A language model can produce a confident number that is wrong. Lesson 5 is entirely about catching that.

Step 1 — Check your privacy settings (2 min)

1. In Claude, open Settings → Privacy. Read whether your chats may be used to improve the models, and set it the way your work requires.
2. Check what your employer, your clients' contracts and your professional duty of confidentiality allow. A setting in an app does not change those obligations.
3. Rule of thumb: if you would not e-mail the file to a stranger, do not paste it into any chat.

Step 2 — Ask for the method, not the data (3 min)

Instead of uploading real rows, describe the structure and give 2–3 invented rows. Copy this prompt:

I have an Excel sheet with these columns:
full_name | phone | email | id_number | note | amount_net
Here are 2 invented example rows:
Ruth Example | 050-1111111 | ruth@example.com | 000000000 | asked for a receipt | 1200
Ben Sample | 052-2222222 | ben@example.com | 000000000 | new client | 800

Give me step-by-step instructions (no macros) to create an anonymized copy:
1. Replace each name with a code like CL-001, keeping a separate key sheet that maps code to name.
2. Remove phone, email and id_number entirely.
3. Keep note and amount_net.
Explain each formula you use in one sentence.

Then run those steps yourself, in Excel or Sheets, on clients-personal-data-demo.csv. The key sheet never leaves your computer.

Step 3 — Your first safe working prompt (3 min)

Paste only the anonymized columns (codes, notes, amounts) and ask:

Here is an anonymized table (client code, note, amount_net).
Group the notes into 3–4 types of request and count how many of each.
Show the rows you put in each group so I can check you.

The last line matters: you are asking Claude to show its working so you can verify it.

Verification checklist

• Nothing with a real name, phone, e-mail or ID number left your computer
• The key sheet (code → name) is saved separately and not shared
• Every group Claude reported matches the rows it listed
• You can explain each formula Claude gave you in your own words

Exercise (the editor below)

Build your personal rules card: three jobs you will ask Claude for, two you keep for yourself, and your privacy rule. Click the ViBot button to have it drafted, then edit it until it is really yours.