Someone in your business is being paid to type numbers into a spreadsheet, and they’re probably copying them from somewhere else - an inbox, Xero, or your job software. Claude can now sit inside Excel and go and get those updates straight from your systems.
This is the full flow I run through Claude in Excel: build a sheet, fill it from where the information actually lives, audit an old one for mistakes, add a dashboard and format it as a report. None of it is technical. No Python, no macros, nothing to build. You just say it.
What is Claude in Excel and what does it cost?
Previously you could get AI to write a formula, but you had to copy it into Excel and keep re-uploading your sheet. Now you can open the Add-ins button in Excel and have Claude sit inside the workbook. It reads the entire workbook, not just the tab you’re on: every tab, the formulas behind the cells and how they’re wired together. And it writes back into the cells, so you’re not copying answers in and out of a chatbot.
You need two things: a paid Claude plan, which is around NZ$40 a month, and a Microsoft 365 subscription with Excel. That’s it. More on the plans in Claude pricing in NZ.
How do you build a spreadsheet with Claude?
Start with a blank workbook. In the video I asked for a project tracker: four active sites, 14 cost codes on each, budget against actual, and a view of where we’re running over. Claude wrote the headers and structure and filled the formulas down, including the VLOOKUPs, in about 90 seconds.
The trick is thinking clearly about what you want the sheet to hold before you ask. Use voice dictation if you want to do a full brain dump.
The most important instruction: ask for formulas, not typed values. Ask an AI for a total and a lot of the time you get a typed number in the cell, which is dead the moment you start using the sheet. Tell it to use formulas and check that the summary tab references the data rather than stale numbers.
To be fair, you could build that tracker yourself in about 20 minutes. The real value is what comes next.
How do you fill a spreadsheet from email, Teams, SharePoint and Xero?
The problem with every tracker I’ve seen in a business isn’t the setup. It’s that this week’s updates are spread across 40 emails, a couple of Teams messages, a SharePoint folder and Xero invoices that three different people have to go and find. Usually a project manager spends their week chasing people to get that information in. That’s the job worth getting rid of.
My Claude is connected to my email, SharePoint, Teams and Xero, so I can ask it to go and get the updates itself. In the demo it pulled site meeting minutes out of SharePoint, found a scaffold hire extension buried in an email thread, and picked up a Teams message about a council RFI that never made it into the sheet. Then it wrote it all in, with the source next to each number.
That source column is not optional. AI can hallucinate, and once a number lands with no origin it’s very hard to go back and check it. Anything Claude can’t source, it doesn’t guess - it marks it as needing a human and puts it at the bottom of the list for you to review.
So the Friday afternoon of typing in job information and chasing staff is gone. What’s left is the review. The time saving isn’t in creating the spreadsheet, it’s in pulling information from lots of places into one place for you to check. The same idea applied to bills and invoices is in automate your accounting with Claude and Xero.
Can Claude audit an old spreadsheet for mistakes?
Nobody actually starts fresh. You inherit a spreadsheet someone built four years ago, they’ve left, and nobody really understands how it works. So get Claude to audit it.
On my example sheet (fake data, but mistakes I’ve seen in real ones) it found four problems in about 50 seconds:
- A total that stopped one row short, so the bottom cost code was never counted.
- A formula someone had typed over, frozen since March.
- A variance percentage divided by the wrong column, so every percentage on the tab was wrong.
- A summary tab out by $18,000 against the actual.
Your staff could find these, but it’s hard to find the time, and someone has to want to go looking. Importantly, Claude doesn’t fix them unless you tell it to. It gives you the list and you decide, which is the right way round - you don’t want it changing your files on its own. Ask it how it would fix them, check the plan, let it make the changes, then review what it did.
How do you build an Excel dashboard with Claude?
Once the numbers are right, a dashboard is worth building. Tell Claude the KPIs you want tracked and it builds it out. Then ask it for suggestions: are there data sources missing, what else would help me make decisions, how could this be better? That’s when you start treating Claude like a business assistant.
Can Claude format a spreadsheet as a report?
This is the part I use most. Tell it exactly what you want:
- Conditional formatting on the variance column, anything over 15% in red.
- Every dollar figure in New Zealand dollars, no decimals.
- Top row frozen, columns wide enough that nothing is cut off.
- Print area set to one page wide.
Or just say “format this like a report I’m sending the CFO in the morning” and attach your branding. Give it your colours, fonts, headers and examples of past sheets, and your spreadsheets look consistent across the team no matter who made them. That’s maybe 40 minutes back every time.
Where can AI spreadsheet work go wrong?
It gets you about 90% of the way. The last 10% is still you, and in a spreadsheet that 10% is the difference between a quote that’s right and one that’s wrong.
AI is probabilistic: the same input can give a different output each time. So validate the outputs and keep a human in the loop, especially for health and safety, pricing jobs and other high-risk work. Anything your business sends out is on you, not the AI. And remember this is the worst AI will ever be - it keeps getting better, fast.
The full flow: build the sheet, fill it from the systems where the information lives, audit the old one, build your dashboard and format it.
