The Formula tab is where the math behind your calculator lives — a real spreadsheet, built into the editor, that turns the values your readers enter into the results they see.
What the Formula tab is
When you open a project and switch to the Formula view, the preview area is replaced by a full spreadsheet. It behaves like the spreadsheets you already know: cells hold numbers, text, or formulas, you can select a cell or a range, and you can paste data in.
The spreadsheet powers your calculator in two directions:
- Inputs flow into cells. Each input block (Input field, Slider, Dropdown, Selection, Toggle) can be bound to a cell, so whatever the end-user enters lands there.
- Results are read out of cells. Each result block points at a cell, and whatever that cell computes is what your reader sees.
The formulas in between are ordinary spreadsheet formulas. See the Formula functions reference for the full list of supported functions.
Reserved columns A–C
The first three columns — A, B, and C — are reserved for Numio. They keep space free for the cells your blocks are assigned to and their labels. When you import a file, the data lands starting at column D, leaving A–C clear. See Importing Excel, CSV, and TSV for how that offset works.
You can type into A–C yourself when building formulas by hand, but keep in mind that imports and block assignments expect those columns to be available.
Autosave
You don't need to save manually. The spreadsheet autosaves a fraction of a second after you stop editing, and it flushes any pending changes when you leave the tab — so your work is never lost on navigation. Undo (Cmd+Z / Ctrl+Z) works as usual for cell edits and imports.
Multiple tabs
A project's spreadsheet can have more than one tab. The first tab is the main sheet — it is the only one that inputs and results connect to. Any additional tabs are static reference data (for example, a rate table that a VLOOKUP reads from). Importing a multi-sheet workbook creates one tab per worksheet automatically. See Working with multiple sheets / reference data.
Where to go next
- Input rows and cell references — how cells are addressed and referenced
- Assigning input blocks to cells — wire an input into the sheet
- Assigning cells to result blocks — show a computed cell to your reader