How to Use Claude With Excel for Client Reports

Ejaz Ahmed, Founder, AI Marketing Foundry. Published 13 June 2026. Last reviewed 31 August 2026.

I work with a lot of data. Client performance reports, campaign analysis, revenue breakdowns - the kind of work that lives in spreadsheets.

For a long time, this was slow. Building a report meant jumping between tools, pulling numbers, formatting tables, writing commentary, checking everything matched. A decent monthly report for one client might take two to three hours.

Now it takes about 45 minutes to an hour. Here's the workflow I use.

The Basic Setup

Claude can work with spreadsheet data in a few ways:

1. Upload a file directly - paste a CSV or export and Claude reads it

2. Copy and paste data - pull a range from Excel, paste it with context

3. Use Claude's computer use - let Claude see and interact with your screen directly

For reporting work, I mostly use a combination of the first two. Where a platform has its own connector, skip the exports entirely: for email data I query the account directly, as described in connecting Klaviyo to Claude with MCP.

What I Actually Do

Step 1: Export the raw data

For a typical client report, this means exporting from Google Analytics, Meta Ads Manager, and Klaviyo. Each as a CSV.

Step 2: Upload to Claude with a clear brief

I give Claude the exports and tell it exactly what I need:

"Here's the data for [Client] for June. I need: total ad spend, total revenue attributed, ROAS by campaign, top 3 performing ad sets, and what changed versus last month. Flag anything unusual."

Step 3: Claude does the analysis, I edit the output

Claude reads the data, does the calculations, and writes the analysis. The format isn't always exactly right first time, and occasionally numbers need a double-check - but the heavy lifting is done.

Step 4: I add my interpretation

This is the bit Claude can't do. It can tell you ROAS dropped 12%. It can't tell you why. I use Claude's output as a foundation and layer in my own view of what the numbers mean and what to do next.

Where This Saves the Most Time

Calculations across multiple sources. Claude handles cross-source aggregations faster than I do manually, especially when data comes in different formats from different platforms.

First-draft commentary. I no longer write commentary from scratch. I ask Claude to draft it in a specific tone, then edit. This alone saves 30-40 minutes per report.

Spotting anomalies. Claude is good at flagging things that look off. "Cost per click on Campaign X is 3x higher than the other campaigns - worth investigating." Things I might miss when scanning a large table.

What You Need to Be Careful About

Check the numbers. Claude occasionally makes errors with large datasets or complex aggregations. Always sense-check totals against your source data before sharing with clients.

Don't remove your judgement. Claude's analysis is descriptive. Your value is the interpretation - why something happened and what to do about it.

Formatting takes iteration. The first output rarely looks exactly right. I usually ask Claude to reformat once or twice before it's presentation-ready. Factor that into your time estimate.

One caveat on all of the above: model behaviour moves. The accuracy guidance in this section was last checked against my own client reports in August 2026. New model versions handle large tables differently, sometimes better, so treat the sense-checking step as permanent rather than something you can drop once a version proves reliable.

Is This For You?

If you produce regular reports and your data lives across multiple tools, this workflow will save you real hours every month, not a few minutes here and there.

The shift isn't about replacing Excel. It's about using Excel to store and export your data, and Claude to interpret it. They each do something well. The same split applies to research work: I hand the gathering to an agent and keep the judgement, which is what happened when I ran a full competitor analysis through Manus.

Start with one report. Upload the data. Brief Claude clearly. The first attempt might be clunky while you figure out how to prompt it correctly. The second will be faster. By the third, it'll feel obvious.

Frequently Asked Questions

Can Claude read Excel files directly?

Claude can read CSV files and pasted spreadsheet data. For Excel (.xlsx) files, exporting to CSV or copying data into the conversation works reliably. Claude's computer use feature can also interact with your screen if you're on a paid plan.

How accurate is Claude when analysing spreadsheet data?

Claude handles most calculations and summaries well but can make errors with large datasets or complex aggregations. Always cross-check totals against your source data before sharing with clients. This guidance was last checked in August 2026 and model behaviour changes between versions.

What kinds of reports can Claude help build?

Campaign performance reports, revenue breakdowns, ROAS analysis, anomaly detection across ad platforms, and any report involving multiple CSV sources with written commentary. Particularly effective for cross-source aggregations.

Do I need a paid Claude plan for this workflow?

A paid Claude plan (Pro or above) gives you higher upload limits and longer context windows, which matters for larger spreadsheets. For regular client reporting, Claude Pro is recommended.

How long does it take to set this up?

The first report takes longer as you learn to brief Claude correctly. By the second or third, the workflow is fast. In my own reporting, a monthly client report went from two to three hours down to under an hour within a few attempts.

Reporting eating your month?

If the same reports come round every month and each one costs you the better part of a day, send me the shape of it: which platforms, how many clients, what the output has to look like. I'll map where the hours are actually going and which parts of the process are worth rebuilding. Start here.

About the author

Ejaz Ahmed founded AI Marketing Foundry after six years at WPP, Publicis and Crafted, running multi-million pound digital portfolios for global brands. He holds an MSc in Data Science and AI and works hands-on with UK SMEs on paid media, email and AI systems. AI Marketing Foundry is a trading name of SDF Ventures Ltd, registered in England and Wales, company number 16371887.