How to use
- Choose the old file and the new file (.xlsx, .xls or .csv). If a file has several sheets, pick the one to compare.
- Choose how to compare. For two versions of the same sheet use Row by row; if the row order differs but there is a unique ID such as an employee or order number, use By key column and pick that column.
- Read the result. Added rows are green, deleted rows are red and struck through, and changed cells are yellow with the old and new values.
- Press Download differences (Excel) to save the result.
Options explained
- Row by row
- Rows are lined up with the Myers diff algorithm, so if rows were inserted or deleted in between, the rows after them still match up instead of all being marked as changed. A pair of rows that is mostly the same counts as changed; completely different rows count as one deleted and one added.
- By key column
- Rows are paired by the value in one column, such as an employee ID, student number, order number or SKU, so the row order does not matter. If a value appears more than once, the occurrences are paired in order.
- Column matching
- Columns are matched by header name, so they can be in a different order. Columns found in only one file are marked Only in old or Only in new. If First row is a header is off, columns are matched by letter (A, B, C…).
- Ignore extra spaces, ignore case
- Differences such as "Smith " vs "Smith" or "ABC" vs "abc" are not counted as changes.
- What is compared
- Cell values — numbers as numbers (8000 and 8000.00 are equal), dates as dates and formulas by their results. Formatting such as fonts, colours and comments is not compared.
Which comparison to use
| Situation | Choose | Example |
|---|---|---|
| Two versions of the same sheet, a few edits and added rows | Row by row | A revised quote, an updated contact list |
| Both files have a unique ID, but the rows are in a different order | By key column | Staff lists from two months (by employee ID), two order exports (by order number) |
| No unique ID and a different order | Sort in Excel first, then Row by row | Two stock counts |
How this differs from Compare PDF Files: that tool compares the text of documents; this one compares spreadsheet data by row and column and tells you exactly which value in which row and column changed.
Frequently asked questions
Can I compare sheets whose rows are in a different order?
Yes. Choose By key column and pair rows by a column that is unique for each row, such as an ID or order number. If there is no unique column, sort both files by the same column in Excel first and then compare Row by row.
Will large files be slow?
Sheets with tens of thousands of rows usually take a few seconds. The page shows the first 500 differing rows; the downloaded file has the full result.
Are my files uploaded?
No. Both spreadsheets are read and compared in your browser and nothing is saved on the site.
Why are changed cells written as "old → new" in the downloaded file?
So you can see what changed in any spreadsheet app. For the raw data, use the old and new files themselves.
Privacy
This tool runs entirely in your browser. Your files and text are processed on your device and are never uploaded to our servers.