Spreadsheets

CSV and XLSX files open in a real grid. Formulas, multi-sheet, sorting — the works.

Opening

Double-click any .csv or .xlsx in the sidebar. It opens as a tab with a full spreadsheet grid.

Editing

Click a cell to select; type to edit; Enter commits.
=SUM(A1:A10) and other standard formulas work.
The formula bar shows the active cell's reference and current formula.
Column headers are clickable for sort ascending / descending.
⌘F searches within the sheet.

Multi-sheet XLSX

.xlsx files can contain multiple sheets. A tab strip appears at the bottom of the editor — click any sheet to switch. Renaming, reordering, adding, and deleting sheets are all supported.

Saving

Changes save back to the original file. For .csv, that's CSV. For .xlsx, that's XLSX — no conversion, no lock files.

Export

File → Export converts the current sheet to CSV or XLSX. Useful when you want a CSV snapshot of a single sheet inside a multi-sheet workbook.

What we don't support yet

Pivot tables
Charts
Macros or VBA
Conditional formatting beyond simple fills

If your workflow needs those, open the file in Excel or Numbers — the file format is untouched, so round-tripping works.