I built an AI Excel tool that never uploads your files. Here's how.

A developer launched FormulaAI, an AI-powered Excel tool that parses spreadsheet files locally in the browser using SheetJS and sends only data summaries to the AI, so full files are never uploaded to a server. The tool offers an Edit Tables feature that applies plain-English instructions and shows changes in a diff view before download, plus a Generate Tables feature that creates spreadsheets from a text description. It is available on a free tier with a monthly quota and a paid unlimited plan.

I just launched FormulaAI — an AI-powered Excel tool with a privacy-first approach. Most AI Excel tools upload your entire file to their servers. Your financial data, customer lists, sensitive business info — all sitting on someone else's server. I wanted something different. Two core features: Edit Tables : Upload Excel → describe what you want in plain English → AI modifies it → see every change in a diff view → confirm and download. Generate Tables : No file needed. Just describe what you want, like "generate a March sales budget with categories, budget amount, actual spend, and variance." AI creates a complete spreadsheet. Files are parsed locally in the browser using SheetJS. Only data summaries are sent to the AI for processing. Nothing is stored on the server. After processing, everything is deleted. Free tier with monthly quota. Paid plan for unlimited usage. Early supporters who signed up before launch get a permanent discount. I'd love to hear your feedback