SheetTutor

SheetTutor is a free site for learning Excel formulas by working through small, practical tasks. The library has 90 of them, from joining text without extra spaces or looking up a price with XLOOKUP to loan cash flows, LAMBDA workflows and regression models, each tagged with the functions involved, a rough time and a level. A lesson has three parts. You try the example, step through how the formula is built on a live worksheet that actually calculates, then do it yourself. Lessons offer a workbook download for practicing in Excel, and there are also courses, workshops, a function reference and a shortcuts list. No account is needed. The privacy page says formulas and worksheet data are processed in your browser, with progress saved in local storage rather than uploaded, and the site says it isn't affiliated with Microsoft.