94% of spreadsheets have errors

It is one of the most-cited numbers in the field, and it should stop us cold: the large majority of business spreadsheets audited in academic studies contained at least one material error. We build companies on these files. Almost none of them are ever tested.

why the errors hide

A spreadsheet has no idea what it is supposed to say. There is no type that says “this column is a date,” no rule that says “this total should match that one,” and no way for the file to flag its own contradictions. A wrong number looks exactly like a right one.

So mistakes do not announce themselves. They sit in a cell, quietly trusted, until a decision is made on top of them.

what a fix looks like

The answer is not “be more careful.” It is to give the spreadsheet a way to check itself.

Explicit types, plus check nodes that catch mistakes before they cost you.

In Braidsheet, columns have explicit types, so an ID stays an ID and a leading zero survives. Check nodes let the model assert what should be true, and surface it the moment it is not. The file stops being a passive grid and starts holding itself to account.