Big spreadsheets freeze many tools. This viewer reads the file in the background and draws only the rows you can see, so scrolling stays smooth.
- Background parsing
- Smooth scrolling
- Filter and sort
Tips for big files
- Use Go to to jump to a row or column, for example B5000.
- Filter a column to its values first, then sort the result.
- Export only the filtered view with Export view as CSV.
- Very large sheets show up to 300,000 rows. The full data is still available through the CSV export.
Why big files are slow elsewhere
Most viewers upload the file, convert it on a server, or build every row on screen at once. Here the file stays on your device and only visible rows are drawn. A big file still needs memory, so close other heavy tabs first.
Frequently asked questions
How big a file can it open?
It depends on your device memory. Files with hundreds of thousands of rows usually work on a laptop.
Is a CSV faster than XLSX?
Usually yes, since CSV needs less parsing.