Claude for Excel can build models, work across tabs, and answer questions with references to cells. This walkthrough starts with a blank planning workbook and checks whether its formulas respond to a small, known change.
Open the official add-in in a supported Excel version
Follow the marketplace link in Anthropic's Claude for Excel documentation. The current listing is Claude for Microsoft 365. Install it, activate it in Excel, and sign in with your supported Claude account. Organizations may deploy it centrally or restrict installation.
Anthropic currently lists Pro, Max, Team, and Enterprise access. Supported clients include Excel on the web and specified Microsoft 365 Windows and Mac builds; check the documentation for your version. This is the Excel add-in experience, rather than downloading an XLSX produced in a regular Claude conversation.
Start in a new workbook with information you are permitted to use. Name the assumptions before asking for formatting. For a supplies estimate, decide whether a quantity is per room, per person, or a fixed allowance. A formula cannot settle that rule for you.
Give the model one small, explicit job
This original fictional fixture estimates stationery for a training session. It is an arithmetic example, not an actual Claude-generated workbook or a supplier quote.
| Input | Value | Meaning |
|---|---|---|
| Rooms | 4 | Rooms receiving supplies |
| Packs per room | 3 | Packs required in each room |
| Price per pack | $12 | Illustrative unit price |
| Fixed delivery | $18 | Charged once |
The expected pack count is 4 × 3 = 12. Supplies cost $144, and the total including delivery is $162. There is no tax assumption in this fixture; do not silently invent one in a real estimate.
Build a small supplies-planning model in this new workbook.
Use an Inputs tab and a Summary tab.
Inputs: rooms 4; packs per room 3; price per pack 12 USD;
fixed delivery 18 USD, charged once. These are fictional test inputs.
First describe the intended cell layout and formula dependencies.
Then create clearly labeled editable inputs. Calculate pack count,
supplies cost, and total including delivery using formulas linked to
those inputs. Do not type calculated totals as constants.
Do not add tax, discounts, minimum orders, or contingency assumptions.
Keep currency labels and units visible. Avoid macros and data tables.
List the input cells and output formulas so I can inspect them.
Check the base case against 12 packs, 144 USD supplies, 162 USD total.
Report discrepancies rather than adjusting inputs to make them match.
Review the proposed layout before using it in an existing workbook. If Claude wants to replace occupied cells, inspect the operation and choose a clear destination. A request to create two tabs does not prove that other tabs remained untouched.
Change an input and follow the dependent cells
Change only Rooms from 4 to 5. The expected result becomes 15 packs, $180 in supplies, and $198 including the same $18 delivery charge. The total increases by $36, which is one additional room's three packs at $12 each.
If the total remains $162, inspect the formula bar and references. An output may be a constant, or a formula may point to an unrelated cell. If delivery rises to $90, the model has multiplied a fixed charge by rooms. The changed-input check catches both kinds of mistake without needing a large dataset.
Restore Rooms to 4 after testing and confirm the base result returns. Then replace the fictional inputs with your actual quantities and quotes. Reconsider the calculation rule when a real supplier introduces minimum packs or multiple deliveries; those conditions change the model.
Keep the workbook understandable after the chat
Label editable cells, include the quote date where relevant, and leave a short explanation of what the total includes. Ask Claude to identify a result's source cells when a relationship is unclear, then click through and read the formulas yourself.
Anthropic lists macros, VBA operations, and Excel data tables as unsupported. Keep this model within ordinary formulas and review the actual workbook before handing it over. For correcting an inherited formula instead, the ChatGPT Excel review workflow shows how to scope a change and compare it with the original.
Save the checked workbook where your team maintains estimates. Tell the next user which cells they can change and that delivery is a fixed charge; those two details explain how to update the estimate without rebuilding it.