How it works
The XLSX Viewer displays Excel spreadsheet files (.xlsx, .xls, .csv) in the browser as a scrollable, sortable table — without requiring Microsoft Excel, Google Sheets, or any other spreadsheet software. Upload a spreadsheet and view its contents instantly.
Receiving an .xlsx file on a device without Excel means either uploading to Google Sheets (a privacy concern for sensitive financial data) or forwarding to a colleague. This viewer renders the spreadsheet locally.
Features: display all sheets (tab navigation for multi-sheet workbooks), cell values with number and date formatting applied, column and row headers, merged cell support, text wrapping, basic fill colors (cell background colors). Sort any column ascending/descending by clicking the column header. Filter rows by typing in the search bar.
Sheet navigation: for workbooks with multiple sheets, tabs appear at the bottom of the viewer — click to switch sheets.
Large files: workbooks with up to ~100,000 rows render smoothly using virtual scrolling (only visible rows are rendered in the DOM). Files with millions of rows may be slow to parse but will eventually load.
Formula display: formulas are shown as their computed cell value (the same value displayed in Excel). The formula expression itself (e.g., =SUM(A1:A10)) is visible by clicking the cell.
Privacy: XLSX parsing runs in the browser using SheetJS. Your spreadsheet data is never uploaded.
Frequently Asked Questions
- The XLSX Viewer is read-only. It displays spreadsheet data but does not support cell editing. For editing, open the .xlsx in Microsoft Excel, LibreOffice Calc, or Google Sheets.
- Click any column header to sort that column ascending. Click again to sort descending. Click a third time to return to the original order. Sorting is a display-only operation — the underlying data is unchanged.
- By default, computed values are shown (the result of each formula). Click any cell to see the formula string (e.g., =SUM(A1:A10)) displayed in the formula bar at the top of the viewer.
- Basic cell background colors (fill colors set manually or from simple conditional formatting rules) are rendered. Complex conditional formatting rules (color scales, data bars, icon sets) are shown as static colors using the values computed when the file was last saved in Excel.