Spreadsheet uses virtualisation to display data, ie only data viewable in a Row x Column viewport is displayed. This improves rendering performance.

Data performance can be improved by 1. Lazy loading data or Infinite scrolling. We have a built-in async hook that does this. 2. Only save pointers to data that is being displayed. So if you have 1M rows, on the JavaScript side, you only load 100 rows in memory and when user scrolls, you can replace this rows with new data. This will make the browser happy. 3. Streaming data from the server similar to google sheets.

But to answer your question, we have a Max row limit of 1_048_576 and max column limit of 16_384