How to compare two Excel files
- Choose both files. A is the original version and B is the new one. They can be Excel, OpenDocument or CSV, and you can mix formats.
- Check how rows are matched. The column that identifies each row (ID, SKU, email…) is picked automatically. If there is none, rows are compared by position.
- Click Compare. Added rows are green, removed rows are red and changed cells are yellow, with the old value struck through.
- Download the report. The Excel file has a summary, the list of differences and a copy of the new file with changed cells highlighted and a note showing the previous value.
Private by design: no upload
Your spreadsheets are read and compared inside your browser. There is no server that receives them: the page only downloads, the first time, the public libraries that read Excel files (SheetJS, PapaParse and ExcelJS). You can check it in the Network tab of your browser's developer tools, or go offline after the page loads and keep comparing.
That makes it a safe choice for customer lists, payroll, inventories, price lists or budgets you should not upload to an unknown website.
What the comparison shows
- Added rowsRows that exist only in the new file.
- Removed rowsRows that were in the original and are gone.
- Changed cellsEach changed value with its before and after.
- New or deleted columnsColumns that exist in only one of the files.
Common uses
- Inventory and price listsSpot new products, discontinued items and price changes between two months.
- Customer and CRM exportsFind new contacts, deleted records and edited emails or phone numbers.
- Payroll and HR listsReview salary changes, new hires and leavers without uploading personal data.
- Budgets and reportsSee exactly what changed between version 1 and version 2 of a spreadsheet.
- Data migrationCheck that an export from the new system matches the old one row by row.
- Supplier catalogsCompare an Excel file with a CSV from a supplier, even with columns in another order.
Why match rows by a key column
Most comparison methods, including formulas in Excel, compare cell A1 with A1, A2 with A2, and so on. If someone inserts a single row at the top, every row below it looks different. Matching by a key column pairs each row with the row that has the same ID in the other file, wherever it is, so only real changes are shown. If no single column is unique, combine two (for example name and date).
How to compare Excel files without a tool
Excel has some built-in options, each with limits:
- View Side by Side (View tab) shows both workbooks next to each other with synchronized scrolling, but you still have to spot the differences yourself.
- A formula in a new sheet, such as
=IF(Sheet1!A1<>Sheet2!A1,"changed",""), or a conditional formatting rule, marks cells that differ. It compares by position, so inserted or sorted rows break it.
- Spreadsheet Compare from Microsoft is only included in some Windows editions of Office, such as Office Professional Plus and Microsoft 365 Apps for enterprise.
Compare Excel matches rows by key, works on any device with a browser and gives you an exportable report.
Known limitations
- One sheet from each file is compared at a time.
- Formatting, comments, charts and macros are not compared.
- CSV files are read as text: “007” and “7” are different values unless the numeric option treats them as the same number.
- Dates are shown as yyyy-mm-dd and compared by value, not by format.