How Grid by Zaweba stays quick on very large sheets
Grid by Zaweba draws only the visible cells, so even a million-row sheet scrolls quickly, and only formulas affected by a change are worked out again.
Spreadsheets often start small and end up big. A sales log gains a row a day for years, an export from a till or a bank arrives with tens of thousands of lines, a sensor writes a reading every few seconds. Grid by Zaweba is built so that size doesn't turn into waiting.
Drawing only what you can see
A screen shows a few dozen rows and columns at a time, however large the sheet. Grid draws only the cells that are visible, so the work it does to show a screen doesn't grow with the size of the sheet. In testing, a screen at row 900,000 of a million-row sheet draws in about 25 milliseconds, quicker than you can notice.
That's why scrolling through a huge list feels the same as scrolling through a small one, and why jumping to the bottom with Ctrl and the down arrow is instant.
Recalculating only what changed
Drawing is half the story; calculating is the other. When you change a cell, Grid works out again only the formulas that depend on it, rather than every formula in the workbook. A change to one row of a long list updates that row's formulas and the totals that use them, and leaves the rest alone. Even a million-row column of formulas stays responsive as you edit.
How text and numbers fit
Grid follows familiar rules for how cells show their contents. Text that's too long for its cell overflows into empty neighbours to the right, so a heading or a note can spread across without you widening the column. When the neighbour has something in it, the overflow stops at the edge of the cell.
Numbers don't overflow, because a number cut off at the edge could be misread. Instead, a number that doesn't fit shows as ####. Nothing is wrong with the value; widen the column or use AutoFit and it appears.
Keeping big workbooks pleasant
Some habits help any large workbook stay quick and easy to work with. Point formulas at the data you need rather than whole columns of empty cells. Use a table for a growing list, so ranges expand with the data. Prefer XLOOKUP or INDEX and MATCH over volatile functions such as OFFSET and INDIRECT where you can, since those make a formula harder for any spreadsheet to keep track of. Freeze the header row so you always know which column you're in.
For summarising a big list, a pivot table is usually quicker to build and read than hundreds of conditional formulas. Filters and Go To help you find your way around, and the status bar gives instant totals of any selection.
Very large files and other formats
CSV files are a common way big data arrives. Grid opens CSV and TSV files with the encoding and delimiter detected automatically, and without damaging the data on the way in. Once imported, save as .zagr or .xlsx to keep formulas, formatting and everything else you add.
Size limits in a spreadsheet are usually about patience more than capacity. In Grid by Zaweba, drawing only the visible screen and recalculating only what changed keeps that patience from being tested.
