Browser · Free
Fast, occasional checks
Best when you have two workbooks in front of you and want a private answer without installing software.
- No account or installation
- Local, interactive comparison
- Built-in safety limits
Local Excel comparison · no workbook upload
See what changed.
Keep the files.
Choose two .xlsx or .xlsm workbooks and compare their values, formulas, types, and displayed text. The work happens in a private browser worker on your device—your workbook bytes are never sent to our server.
- Runs on Windows, macOS, and Linux
- Match rows by a stable ID
- Export HTML or JSON locally
Free browser comparator
Compare two workbooks
Select two workbooks to begin. Nothing is uploaded when you choose a file.
Local result
Comparison result
Private by design
Selecting is not uploading.
Modern browsers can give a page temporary, read-only access to files you explicitly select. Workbook comparison transfers those bytes directly into a background worker inside this tab, parses the workbook there, and returns only the result to the page.
The comparison page contains no advertising, third-party analytics, cloud-storage integration, or upload form. After a real comparison finishes, it sends this site a small usage event containing only the comparison mode and change count so the operator can receive a Telegram notification. Workbook names, paths, bytes, values, formulas, and reports are never included. Close the tab to release the in-memory workbooks.
Your files→Browser memory→Local report
Dependable review
Focus on the workbook evidence that matters.
A clear record of meaningful changes
- Added and removed worksheets
- Cell values and calculated values stored in the file
- Formula text, cell type, and formatted display text
- Positional comparison on every matched sheet
- Optional keyed-row comparison on one sheet
- Self-contained HTML and structured JSON reports
Designed for practical workbook workflows
Compare ordinary worksheets by position or match a table by a stable ID such as order number, account code, or SKU. Review the result in the page, then retain the same evidence as an HTML or JSON report.
Free now, automated when needed
The browser answers “what changed?”
The CLI makes sure you never miss it.
CLI · Personal license
Repeatable checks and automation
Best for generated reports, recurring checks, larger workflows, and build pipelines. A command can produce reports and return an exit code when a workbook changes.
- Run locally from PowerShell, Terminal, scripts, or CI
- Automate the same comparison every time
- Keep working without opening a browser
Useful details
Before you compare
Why use a key such as Orders:A?
A normal positional comparison treats a record moved from row 10 to row 11 as many cell changes. If column A contains a stable order ID, keyed mode finds that same order in either row and compares the record itself. Blank keys are skipped and the first duplicate key wins; the report warns you when this happens.
Does this send names or workbook values to Telegram?
No. After a real comparison finishes, WorkbookLens reports only whether it used positional or keyed matching, whether differences were found, the number of differences, and the completion time. The server forwards that operational event to the operator's private Telegram chat. Workbook names, paths, values, formulas, and generated reports remain only in your browser.
Why does the browser version have limits?
An Excel workbook is a compressed ZIP file. Limits on file size, declared expanded size, cell count, and run time protect your browser from damaged files and decompression bombs. For the same reason, the online version rejects the data-descriptor ZIP format used by some streaming workbook exporters; those otherwise valid files can be compared with WorkbookLens CLI. The background worker also keeps heavy parsing away from the page controls.
Can I open an .exe by double-clicking it?
The paid download is a command-line tool, not a desktop window. On Windows, open PowerShell in the extracted folder and invoke the executable with .\workbooklens.exe "before.xlsx" "after.xlsx". There is no extra diff word. The download guide includes complete Windows, macOS, and Linux examples.