My tools

XLSX viewer & editor

Open a workbook, edit cells, download a new copy.

Excel workbook

Drop an .xlsx here

or choose a file — every sheet is read in this tab, nothing is uploaded.

How to use it

  1. Drop an .xlsx onto the card or pick one with “Choose .xlsx”. Every visible sheet appears as a tab; the first sheet opens at once, and nothing leaves your device.
  2. Click a cell to select it, then double-click, press Enter or F2, or just type to replace its value. Enter commits and moves down, Tab commits and moves right, Esc cancels. The bar above the grid shows the cell address (A1) and the raw value; formulas show as =SUM(...).
  3. Use the toolbar to insert or delete rows and columns, rename a sheet, and undo up to 50 steps. When you are done, “Download .xlsx” writes a new workbook called <name>-edited.xlsx — the file you opened is never modified.

Example

Sample grid

     A          B            C          D
1    Order ID   Customer     Amount     Date
2    1001       Ann Lee      120.5      2025-08-01
3    1002       Ben Carter   80         2025-08-02
4    1003       Chen Wei     =C2+C3     2025-08-03

After editing

After “Load sample”, change B2 to “Ann Lee (called)” and download workbook-edited.xlsx:
B2 = Ann Lee (called)
A2 is still the text 1001 (leading zeros survive)
C4 is still the formula =C2+C3; Excel recalculates it to 210.5 on open
The header row is bold and frozen; D2:D4 stay dates

The sample is a real 4-column, 5-row workbook: row 1 is the header, C4 is a formula with no cached value, and D2:D4 are ISO dates. Load it with “Load sample” and try the steps above.

Rules, limits and known issues

  • Formulas are shown, not calculated. The grid shows the value cached in the file; changing a referenced cell does not update them. Safe formulas are written back and Excel recalculates them on open (fullCalcOnLoad). Array/data-table formulas, formulas on a sheet after inserting or deleting rows/columns, the affected shared group after editing it, and cross-sheet formulas after renaming are saved as values, with a counted notice.
  • The download is a new workbook, not the original. Fonts, colours, borders, number formats (thousands separators, percentages, currency, decimals), row heights, merged cells, conditional formatting, data validation, comments, images, charts, hyperlinks, named ranges and pivot tables are not carried over. Column widths are re-estimated from the content.
  • Limits are hard: 10 MiB per file, 30 sheets or 1,000,000 cells per workbook, and 50,000 rows, 200 columns or 500,000 cells per sheet. Above that the file is refused with an explicit message instead of freezing the tab. The grid draws 100 rows per page; “of N rows” counts to the last non-empty row and every row stays in the file.
  • Hidden and very hidden sheets are not shown as tabs and cannot be edited here; they are written back with their state and their values. Formulas on them are kept, but formatting is not. If every sheet is hidden, the first one is shown so the editor is not empty.
  • Dates are recognised only when the cell already is a date and you type ISO (2025-08-01 or 2025-08-01 12:00:00); other input becomes text. In a blank cell only a strict number becomes a number, so 0001, 1,000, 12% and $5 stay text. TRUE/FALSE stays text unless the cell was already boolean.
  • Undo covers cell edits, row/column inserts and deletes, and renames, up to 50 steps; a new action clears the redo stack. “Revert” re-reads the original bytes and also clears both stacks. “Clear” returns to the empty state and cannot be undone.
  • One .xlsx at a time. Sorting, filtering, find & replace, multi-cell copy/paste, fill handles, merged-cell editing, formula evaluation, CSV import/export and saving back to the original file are out of scope. Nothing is uploaded, stored or logged.

Other ways to work with tables and text.

Excel dedupe

CSV viewer