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Excel diff online: compare spreadsheet changes fast

You have two Excel files open and need to find what changed between them. Excel diff online tools help identify added, deleted, and modified rows and cells without manual checking.

Compare two Excel files online and get a detailed list of added, deleted, and changed cells instantly.

Drop your file in and ask a question — no account needed.

Upload your spreadsheet.xlsx .xls .csv — free to try, no account

Or start with

How can I see what rows were added or deleted between two Excel files?Is there a way to compare two XLSX files without installing software?Why does my diff tool show changes in merged cells incorrectly?Can I get a summary of all cell value changes between versions?How do I handle differences caused by numbers stored as text?

What this export contains

Sheet Name
Row Number
Column Name
Old Value
New Value
Change Type

What usually goes wrong with it

  • Manual comparison is slow and error-prone

    Checking differences by eye or with simple filters misses subtle changes or requires tedious row-by-row scanning.

    DataMimi DataMimi scans both Excel files in the browser and highlights added, deleted, and modified rows automatically.

  • Excel’s built-in compare tool is limited

    It requires desktop installation and doesn’t run inside the browser, making quick online checks impossible.

    DataMimi It works fully online, no installation needed, letting you compare XLSX files anywhere.

  • Merged cells and hidden rows disrupt diff results

    These features cause alignment issues, making it hard to tell if a row was deleted or shifted.

    DataMimi Merged cells are detected and handled to keep row alignment correct during comparison.

  • Data type mismatches hide changes

    Numbers stored as text or date formats differing between files cause false positives or missed updates.

    DataMimi DataMimi checks data types and normalizes numbers stored as text to avoid false change reports.

  • Large files slow down online tools

    Many online diff tools struggle with big Excel files, timing out or failing to load full data.

    DataMimi The tool is optimized to handle large Excel files without timing out or losing data.

Common questions

What does excel diff online mean?

It means comparing two Excel files directly in a browser to find differences without desktop software.

Can DataMimi detect added and deleted rows?

Yes, it automatically lists rows added or removed between two versions.

Does DataMimi handle merged cells correctly?

It recognizes merged cells and adjusts the comparison to avoid misalignments.

Can I see which exact cells changed values?

DataMimi reports each changed cell with old and new values side by side.

Is there a limit on file size for online diff?

DataMimi can process large files efficiently, but extremely large files may take longer to load.

Try it with your own file

DataMimi reads the file you actually have — merged cells, headers below row one, totals pasted at the bottom — and shows which rows and columns every number came from.

Ask about your file

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