Upload your original spreadsheet on the left and the updated version on the right, then click Find Differences. Changed cells are highlighted in yellow with the old value shown in parentheses. Added rows are green, removed rows are red. Works with .xlsx, .xls, .csv, .ods, and more. Nothing is ever uploaded to a server - all processing runs in your browser.
How to use this tool
Drop your original (older) spreadsheet into the left panel and the revised (newer) version into the right panel. Then click "Find Differences." The diff output appears below with every change color-coded by type.
If either file contains multiple sheets, tabs appear below the file preview so you can select which sheet to compare. Each side selects its sheet independently - useful when sheets have been renamed or reordered between file versions.
The Swap button exchanges the contents of both panels without re-uploading. The Sample button loads a short example spreadsheet. The Copy Diff button copies the full result to your clipboard as tab-separated text.
Reading the color coding
| Color | Meaning | Detail |
|---|---|---|
| Yellow | Changed row | At least one cell in this row has a different value. The old value is shown in parentheses next to the new value. |
| Green | Added row | This row exists in the changed (right) file but not in the original (left). It was added. |
| Red | Removed row | This row exists in the original (left) file but not in the changed (right). It was deleted. |
| None | Unchanged row | Every cell in this row is identical in both files. |
Supported formats
| Format | Extension | Notes |
|---|---|---|
| Excel Workbook | .xlsx | Modern Excel (Office 2007+). Most common format. |
| Excel 97-2003 | .xls | Legacy binary format. Widely used in older enterprise systems. |
| Excel Macro-Enabled | .xlsm | Macros are ignored; cell data is compared normally. |
| CSV | .csv | Comma-separated values. Common export from databases and web apps. |
| Tab-delimited text | .txt | Tab-separated values. Common from legacy software. |
| OpenDocument | .ods | Used by LibreOffice Calc and Apache OpenOffice. |
Use cases
Financial reporting and reconciliation
Compare monthly or quarterly financial reports between the draft and the signed-off version. The diff immediately shows every cell that changed - useful for catching last-minute edits, formula overrides, or figures manually adjusted after the original was shared.
Data migration verification
After migrating data between systems, export the source data and the migrated data as CSV or Excel and compare them. The diff confirms that every row transferred correctly and no values were dropped, truncated, or reformatted differently.
Pricing sheet and inventory updates
When a supplier sends an updated price file, compare it against the previous version to see which SKUs changed price, which were added, and which were removed - without reading both files manually.
How the comparison works
Both files are parsed entirely in your browser using SheetJS. No data is sent to any server. Rows are matched by position: row 1 from the original is compared to row 1 from the changed file. Within each matched row pair, every cell is compared individually by its string representation.
Row matching and limitations
This tool uses positional row matching: row N in the original is always compared to row N in the changed file. If a row was inserted in the middle, every row after it will appear as "changed" due to the position shift. For best results, sort both files by a unique identifier column before uploading, or ensure new rows were only appended at the bottom.
Common mistakes
Uploading files in the wrong order
The left panel is "Original" and the right panel is "Changed." If the output looks backwards, use the Swap button to exchange both files without re-uploading.
Formula values vs. formula text
This tool compares the calculated cell values, not formula strings. If a formula changed but the result is still the same number, the cell will show as unchanged. Use a native Excel tool to compare formula text.
FAQs
How do I compare two Excel files?
Upload your original .xlsx file on the left and the changed version on the right, then click Find Differences. Changed cells are highlighted in yellow with the previous value shown in parentheses.
Is my data safe?
Yes. All processing happens entirely in your browser. Your files are never uploaded to any server, never stored, and never shared.
Can I compare an .xlsx against a .csv?
Yes. The tool normalizes all supported formats to the same internal grid structure before comparing, so you can mix formats freely.