Anthropic wants Claude to be the place where we do office work. The San Francisco-based OpenAI competitor has launched Claude Sheets, Claude Whiteboards and Claude Data, which let you build spreadsheets, plan projects on a shared board and turn numbers into dashboards without closing your chat with the AI. Naturally, Microsoft’s stock closed 2.2% lower on the day of the announcement.
Of course, the headlines took every chance to declare that Excel is in trouble. But Anthropic admits that Claude Sheets can’t replace Excel: “When you need the full functionality of Excel, you can export your file to .xlsx or CSV, or use Claude for Excel(opens in new tab).”
The way I look at it, the greater threat (for Microsoft) is a new feature that opens apps like Adobe, Atlassian, and Box inside Claude, so you may not need to open Microsoft’s apps to start your work. Should Redmond, the poster child of enterprise software, be worried at all?
Claude wants you to do the work without leaving the chat
If you have watched Anthropic’s launch video, instead of some viral tweets and headlines, you would’ve already gotten a better picture:
A fictional bakery is planning a “Huckleberry Pie” launch, and someone tags Claude on a whiteboard asking for an illustrated timeline “from locking the flavor to holiday delivery.” Claude, as expected of any AI, lays out the tasks and deadlines on the board.
When someone asks Claude Sheets to draft a forecast for pre-orders using last year’s numbers from another tab, it builds the spreadsheet, which is nothing difficult for the AI, but having its own version of a spreadsheet inside the app is the big news here, because a user wouldn’t have to open Excel.
Finally, Claude Data crunches those numbers into a dashboard that shows Huckleberry being the top pre-ordered pie, and even offers to redo it as a scrolling story or a short video, because, apparently, people lost the ability to read graphs?
Jokes aside, I do not know any bakeries that do this kind of planning, but if they do, this might’ve taken several days of work, and multiple tools (including Excel, and maybe even a PowerPoint presentation if they’re fancy)
Anyway, the plan, the spreadsheet, and the report all came from the conversation, and that’s the whole point…
According to Anthropic, Claude Sheets supports tabs, formulas, formatting, and drop-downs, outlines every edit it makes, and lets your team edit the sheet along with Claude. You can export it as an .xlsx or CSV file. Claude Data, formerly Claude Dashboards, is now generally available on paid plans and connects to data warehouses and CRMs. Sheets and Whiteboards are in beta on paid plans.
Then there are the interactive connectors, which open full versions of apps like Adobe, Atlassian, Box and Notion next to your conversation. I was amused by one reply under Claude’s post on X: “At this point the chat is the office lol.”
Anthropic also announced Claude Meetings, which joins video calls, takes notes, and updates documents as people talk. But it only works with Google Meet at launch, according to TechCrunch, so it’s not a Microsoft Teams rival, at least for now.
Microsoft won the Office war by being the default, and the free Google Sheets couldn’t change that
Although synonymous with Microsoft, they didn’t invent office software. In the early 1990s, Lotus 1-2-3 ruled spreadsheets and WordPerfect was the de facto word processing. Then the industry moved from DOS to Windows, and Microsoft sold Word and Excel into a single suite. That was the genius move.
Microsoft Office shifted market share away from Lotus and WordPerfect. And by 1995, the year Office 95 launched with Windows 95, Microsoft had 89.4% of the office suite market, according to Dataquest.
Like someone on X said, Microsoft won because every teen with a CD burner installed Office for the whole family. Piracy probably helped with familiarity, but the shift to Windows did a lot more for Office.
Then came Google. On June 6, 2006, Google launched a limited test of Google Spreadsheets, a free web app for “basic spreadsheets that need to be shared or updated by several contributors.” The New York Times called it Google “stepping up its attack on Microsoft’s core business.” Twenty years later, Anthropic’s Nicholas Lin told Bloomberg that Claude Sheets is “still a relatively basic product.” Sounds familiar?
Excel, of course, survived. Microsoft’s Excel head Brian Jones says Excel on the web session counts grew 10x in six years, which was a surprise to me, as I have never seen anyone use Excel online. Also, people don’t choose just a spreadsheet app. They also pick whatever works with their files, colleagues, and company systems.
Copilot got to Excel first, and Microsoft already moved Office into Copilot
Whether we liked it or not, Microsoft beat Anthropic to AI in Excel. Copilot in Excel became generally available on September 16, 2024. Claude learned to create and edit Excel files on September 9, 2025, and the Claude for Excel add-in arrived in beta on October 27, 2025.
But being first didn’t earn Microsoft any goodwill. From what I’ve seen, people were annoyed by the Copilot button showing up everywhere in Office, while Claude working inside Excel felt like a relief.
Ironically, Microsoft is a Claude customer too. The company added Claude models to Microsoft 365 Copilot in September 2025, and Copilot in PowerPoint is getting Anthropic’s Sonnet 5.5 model as part of the October updates.
Microsoft, being first in many things (despite not being good at all of them), also saw the chat-first shift coming. In October, Redmond announced Office in Copilot, which lets you create, edit and collaborate on Word, Excel and PowerPoint files inside the Copilot app. In the announcement, Microsoft wrote that “Microsoft Office has defined productivity for the PC era.”
And Satya Nadella, who now calls the updated Copilot an OS for work, predicted all this back in December 2024. On the BG2 podcast, he said, “Hey, why do I need Excel?” and that the very notion of applications would “collapse” in the agent era. Well, Anthropic seems to have taken him at his word.
Microsoft’s real moat is SharePoint, Teams and Entra
Merill Fernando, a former Microsoft Entra product manager, wrote on X that Microsoft “can’t keep up with the pace that Anthropic is moving,” although “they have a huge moat.”
One reply under his post argued that the moat is SharePoint and Teams, not Word or Excel. One IT service provider said there’s “nothing properly comparable to Entra and Intune anywhere.” Replacing a spreadsheet is easy. But it’s nothing like replacing email, identity, device management and compliance for thousands of employees.
Claude Sheets isn’t ready for that world yet. Its help page lists a 100,000-cell limit, no pivot tables, and no support for macros, VBA, Power Query or DAX. The beta also doesn’t support HIPAA, customer-managed encryption keys or zero data retention, which is a big deal for any company with sensitive data.
Microsoft’s numbers look healthy, too. Microsoft 365 has more than 450 million paid commercial seats, and paid Copilot seats crossed 30 million in July, roughly 6.7%.
However, Microsoft keeps giving people reasons to look elsewhere. Microsoft 365 business and enterprise plans got a price hike on July 1; Office 2021 lost support on October 13.
The company infamously kept renaming Office every few years just to make them like the new thing users need. And now the Microsoft 365 Roadmap is called “AI at Work.”
Microsoft also retired the standalone Whiteboard apps on October 16, less than a month before Claude Whiteboards was born. Whiteboard still works in Teams and on the web, but the timing is funny.
You might’ve seen news of how Governments are moving away from Microsoft, although for different reasons. Germany’s Schleswig-Holstein has moved almost 80% of its state workplaces to LibreOffice in the name of digital sovereignty.
With that said, I noticed people aren’t nearly as angry at Microsoft as they were in 2025. Many replies defended Office, and economist Ernie Tedeschi made an interesting counterpoint: “Excel is the tardigrade of software. You cannot kill it.”
Office may survive, but the app window might not
Anthropic isn’t the only one in this race. OpenAI added Pages, collaborative slides and Dots agents to ChatGPT at DevDay in September, and Google has Gemini built into Workspace.
Microsoft also profits from Anthropic’s growth. It committed up to $5 billion to Anthropic last November, and Anthropic agreed to buy $30 billion of Azure compute. So, some of Claude’s growth turns into Azure revenue for Microsoft.
Claude Sheets can’t handle advanced Excel work, and no company will move 100,000 employees because an AI builds a tracker faster. But if people start opening Claude first, building their files there and pulling their other apps into the chat, Microsoft risks becoming the plumbing behind the workflow, from a state where it owned the apps people open every morning.
Microsoft isn’t about to lose the Office space. The company should be focusing on making Copilot good enough that people don’t decide to start their work somewhere else.
