About SuperSheet

SuperSheet turns a messy spreadsheet into a presentable one. You drop in an .xlsx or .csv, it reads the structure, proposes a set of changes, and hands back a formatted file. That is the whole product.

Why it exists

Plenty of people have to produce spreadsheets without ever having wanted to become spreadsheet people — freelancers sending a client a summary, a small business owner doing a budget, someone prepping numbers for a boss. The data is usually fine. The presentation makes it look like it is not, and fixing that by hand means knowing which of Excel's several hundred options actually matter.

Every existing tool I found was either a formula generator, an add-in you install into Excel, or a spreadsheet you migrate your whole team to. None of them solved “this specific file needs to look good by Thursday”.

How it works

Your file is parsed in your browser using JavaScript, transformed in your browser, and written back out as a real .xlsx in your browser. There is no upload endpoint. Nothing is stored, because there is nowhere to store it.

The AI features are the one exception, and they are opt-out on the drop screen. When they are on, the sheet’s contents are sent to the language-model provider for that single request so the assistant can answer about your actual rows rather than guess from a sample. Nothing is retained. When they are off, no request is made at all and the formatter still does its full job on local rules.

Who built it

I'm Mark Fulton — I build and launch small web products. More about me on the author page, and the reasoning behind the formatting choices is on the blog.

Bug reports, feature requests and files that broke it are all welcome at hello@supersheet.app.