Proton Launches a Spreadsheet App That’s Actually Private

According to Engadget, Proton has officially launched Proton Sheets, a new spreadsheet application that joins its existing privacy-focused productivity suite. The tool offers real-time collaboration and lets users control who can view or edit files, accessible from any device including mobile. It supports importing data from CSV and XLS files and includes support for commonly used calculation formulas. A core part of the pitch is its privacy promise: user information won’t be used for AI training. Critically, all data is protected with end-to-end encryption by default, a feature Proton’s press release explicitly notes is absent from competing products like Google Sheets and Microsoft Excel.

The Privacy Play

Here’s the thing: building a spreadsheet app isn’t the hard part. The hard part is making it work smoothly while everything is encrypted. Real-time collaboration with end-to-end encryption is a serious technical challenge. Every keystroke, every formula change, has to be encrypted on your device, synced, and decrypted on your collaborator’s device, all without introducing lag or sync conflicts. Proton‘s betting that for businesses, journalists, or anyone handling sensitive data, that trade-off for security is worth a potential performance hit compared to the blazing-fast, but data-hungry, Google Sheets.

The Bigger Battle

So, is this enough to get people to switch? I think that’s the real question. For the already-converted Proton Mail user, this is a huge deal. It means you can finally build a workflow entirely within Proton’s encrypted ecosystem—email, calendar, drive, VPN, and now spreadsheets. That’s a compelling suite. But for the average person or company neck-deep in Google Workspace or Microsoft 365, the friction of moving complex spreadsheets and retraining teams is massive. Proton Sheets isn’t just selling a tool; it’s selling a philosophy. And in a world where data scraping for AI is rampant, that philosophy is getting louder.

The Limitations and The Future

Look, let’s be real. It probably won’t have the sheer depth of features or the vast library of third-party add-ons that Excel has cultivated over decades. And that’s okay. Proton’s not trying to beat Microsoft at its own game. It’s creating a parallel market where privacy is the primary feature. The support for common formulas and basic import/export is the minimum viable product to be useful. The real test will be how well it handles complex, multi-sheet workbooks with lots of collaborators. If it can do that reliably while staying encrypted, then they’ve got something genuinely disruptive. Basically, they’re proving that productivity software doesn’t have to mean giving up your data.