Open an original and a changed workbook to see every difference: changed cells with old and new values, inserted and deleted rows, and added or removed columns and sheets. Match rows by a key column such as an ID, by automatic row alignment, or by cell position, then download a color-coded diff report.
Last updated:
Original file
Sample: inventory_v1.xlsx
Changed file
Sample: inventory_v2.xlsx
Drop .xlsx, .xlsm, .csv or .tsv files on the boxes. Files never leave your browser.
added rowremoved rowchanged cellold → new
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How to use the Compare Excel Files
Open the original workbook on the left and the changed workbook on the right (or drop the files). A sample comparison is shown until you do.
Pick the sheets to compare. Sheets with the same name are paired automatically and listed with their number of changes.
Choose how rows are matched: by a key column (ID, SKU, email) when rows may be re-sorted, by row alignment to detect inserted rows, or by cell position for fixed layouts.
Fine-tune the rules: ignore case or spaces, set a number tolerance, exclude a column such as a timestamp, or compare formulas too.
Review and export: filter to changed, added or removed rows, open the cell change list, and download the diff report XLSX.
Choosing how rows are matched
Situation
Key column
Row alignment
Cell position
A row was inserted in the middle
1 added row
1 added row
Every row below looks changed
The sheet was sorted differently
No false changes
Many moved rows show as added + removed
Most rows look changed
No unique ID column
Not possible
Best choice
Works if rows never move
Fixed form or template (values at fixed cells)
Not suitable
Works
Best choice
A value in a row was edited
Changed cell
Changed cell
Changed cell
Row alignment works like a text diff: rows that are identical in both sheets are lined up (using the Myers longest-common-subsequence algorithm), and the leftover rows between two matches are paired as changed rows. Extra rows without a partner are reported as added or removed.
What counts as a difference
Values, not formatting. Fonts, colors, borders, column widths and number formats are ignored. A cell formatted as currency ($1,200.00) and a plain 1200 are the same value.
Numbers are compared as numbers, so 5, 5.0 and 5.00 match. Set a tolerance such as 0.01 to ignore rounding noise from recalculated formulas.
Dates are converted from Excel serial numbers (both the 1900 and 1904 date systems) to YYYY-MM-DD, so a date and its text form compare correctly.
Formulas are compared only when you tick Compare formulas. Values are the results Excel saved with the file; if a workbook was saved without recalculating, the stored values may be stale.
Columns are matched by header name when the first row is a header, so an inserted column is reported once instead of shifting every value to the right.
Tips
Exclude columns that always change, such as Last updated or Modified by, with Ignore column.
Comparing CSV exports instead? The CSV Diff Checker also accepts pasted text. To look inside a single workbook, use the Excel Viewer.
Legacy .xls and .ods files need the SheetJS library, which loads from a CDN on first use. .xlsx, .xlsm, .csv and .tsv are read without any library.
Frequently asked questions
How do I compare two Excel files for differences?
Open the original file on the left and the new version on the right. Sheets with the same name are paired, and the tool shows each changed cell with its old value crossed out and the new value next to it. Added rows are green and removed rows are red.
Which matching mode should I use?
Use Key column when each row has a unique identifier such as an ID or SKU: rows are found by key, so sorting differences don't show up as changes. Use Row alignment when there is no key but rows were inserted or deleted; it lines up identical rows like a text diff. Use Cell position for forms and fixed layouts where every value has a fixed address.
Does it compare formulas or only values?
By default it compares the values stored in the file (the results Excel last calculated). Tick Compare formulas to also flag cells whose formula text changed, for example =SUM(B2:B9) becoming =SUM(B2:B10), even if the result is the same.
Why do dates or numbers look different from Excel?
The tool compares the underlying values, not the display format. Dates are shown as YYYY-MM-DD, and numbers are shown without currency symbols or thousands separators, so a change of format alone is not reported as a difference. Use the number tolerance to ignore tiny rounding differences.
What is in the diff report XLSX?
A Summary sheet with counts per sheet, a Changes sheet with one row per changed cell (sheet, cell address, row, column, old and new value) plus added and removed rows, and one color-coded Diff sheet per compared sheet in which changed cells show old → new.
Can I compare files with different sheet names or column orders?
Yes. Pick any sheet from each file in the sheet menus. When the first row is a header, columns are matched by header name, so inserted, deleted or reordered columns are detected instead of shifting every value.
Are my spreadsheets uploaded?
No. Both workbooks are unzipped and compared in your browser with JavaScript, and the report is generated locally. Nothing is sent to a server.
Are all the tools on FreeToolCabin tested for quality and accuracy?
Yes! Every tool on our site undergoes automated Q/A testing in real browser environments to ensure high precision, correct output, and zero errors. If you happen to spot a bug or have a suggestion, please contact us at [email protected] and our team will review it right away.