Excel Diff Checker
Runs locally in your browserCompare two Excel workbooks sheet by sheet, row by row and cell by cell
Choose an Old Workbook and a New Workbook, or load the sample pair.
Old Workbook
Drop an .xlsx file here or browse.
New Workbook
Drop an .xlsx file here or browse.
Limits: .xlsx only · 15 MiB per file · 50 sheets per workbook · 250,000 cells across both workbooks · rows up to 100,000 and columns up to 1,024 (AMJ). Runs locally in your browser: workbooks are not uploaded, formulas are not recalculated and external links are never opened. Values are the results saved in each file and may be stale if a workbook was not recalculated before saving. Formatting, named ranges, merged-cell layout and charts are not compared; merged ranges use their top-left cell.
No comparison yet
The workbook summary, sheet tabs and spreadsheet-style diff grid appear here after Compare.
Excel Diff Checker
Compare two Excel .xlsx workbooks locally and see added or removed sheets, rows and cells, changed values and changed formulas. Add the Old Workbook and the New Workbook, choose how sheets and rows are matched, then select Compare. Use the sheet tabs and filters to review the spreadsheet-style grid, select any cell to inspect old and new values and formulas, and export a Markdown report, CSV summary or JSON diff.
Position and Key Column Match
Position Match compares the same coordinates in both workbooks. Key Column Match aligns rows by a column such as ID, Email, SKU or Invoice Number, so inserted, deleted and reordered rows are reported without cascading false changes. Blank or duplicate keys are reported with their rows instead of being guessed.
Privacy
Workbooks are processed in a background worker in your browser and are never uploaded. Formulas are compared as text and are not recalculated; values are the results saved in each file. Only comparison options are remembered on this device.
Limits
Supports .xlsx only. Each file can be up to 15 MiB with 50 sheets; both workbooks together can hold 250,000 cells, up to row 100,000 and column 1,024. Packages are checked for unsafe paths, encryption and decompression bombs before parsing.
