The desktop app
Pick two workbooks — or two folders — and press the button. The highlighted files and the report open automatically when the comparison finishes.
Spot every difference
between two Excel files.
Hogandiff compares two Excel workbooks and highlights every changed cell. There is no key column to configure — and no key row either: inserted, deleted and moved rows and columns are detected automatically, and you get back color-highlighted copies of both files plus a comparison report.
Windows / macOS · .xlsx .xlsm .xls · free · no installer
Changed cellsAdded / removed rows and columnsMoved rows and columns
What makes it different
Built for the dense, grid-like spreadsheets that are used as documents rather than databases.
Two axes, not one
Hogandiff works out which rows and which columns correspond to each other, at the same time. Insert a column and a text diff reports the whole line as changed; here it is absorbed, and you see only the cells that really differ. Neither axis needs a key — no key column, no key row — and when the guess is not what you meant, you can weight or pin rows and columns by hand.
Results you can open in Excel
You get copies of both workbooks with the changed cells colored in, plus a separate report workbook that lists the differences sheet by sheet. Nothing to learn: the result is an ordinary spreadsheet.
Old and new Excel formats
.xlsx, .xlsm and legacy .xls are all supported, including comparing one format against the other. Password-protected workbooks can be compared from the desktop app and through the MCP server.
Everything stays on your machine
The comparison runs entirely on your computer; the contents of your files are never sent anywhere. Microsoft Excel is not required to run a comparison, and there is no runtime to install.
Three ways to use it
The same comparison engine, in the shape that fits the job.
The command line
hogandiff old.xlsx new.xlsx compares without opening a window and reports the outcome as an exit code (0 no differences, 1 differences found), so it drops into scripts and Git difftool setups.
Your AI assistant
A Model Context Protocol server is bundled, so assistants such as Claude can run the comparison and talk you through what changed — including re-running it with different weights when you ask.
What it looks like
Two workbooks in, two colored workbooks and a report out.
Download
The current version is v1.5.0. It is free for personal and commercial use. There is no installer — unzip the folder and run it.
Windows
10 (1607+) / 11macOS
14 Sonoma or laterGetting started
- Download the file that matches your operating system and CPU architecture.
- Unzip it and move the whole folder wherever you like, keeping its contents together.
- Run
方眼Diff.exe(Windows) or方眼Diff.app(macOS) from inside that folder. The command-line tool (hogandiff) and the MCP server (hogandiff-mcp) sit next to it.
The Windows executables are not code-signed, so the first launch may show“Windows protected your PC”. Choose More info →Run anyway to continue. On macOS the app is notarized by Apple, so it starts without that step.
On first launch the app asks you to accept the license agreement, and asks separately whether you are willing to send error reports. That second checkbox starts out ticked; clear it there if you would rather not, or change your mind later in the settings dialog. Error reports never contain the contents of the files you compare.
System requirements
- Windows 10 (version 1607 or later) or Windows 11, on x64 or Arm64 — Windows on Arm has only been verified on Windows 11
- macOS 14 (Sonoma) or later
- Native builds for x64 (Intel / AMD) and arm64 (Apple Silicon, Windows on Arm)
- No installer and no .NET runtime to install
- Microsoft Excel is not needed to run a comparison — only to open the results
What it does not do
Hogandiff deliberately keeps its scope narrow, and it is better to know the edges before you download it:
- It compares cell contents (values or formulas), cell comments, and the text inside shapes, text boxes and SmartArt. Formatting is not compared — fonts, fill colors, borders, number formats, the appearance of shapes, charts and macros are all out of scope. The single exception is strikethrough, which is detected.
- Objects that contain no text (arrows, lines, images) are not tracked.
- The
.xlsbformat is not supported, and neither are sheets that are not worksheets (chart sheets, dialog sheets). - Password-protected workbooks can be compared from the desktop app and through the MCP server, but not from the command line: it cannot open them, and skips them automatically when it walks a folder.
- Hogandiff is free but not open source. Use is governed by its license agreement.
Languages and support
The application itself speaks English, Japanese and Chinese. It picks a language from your operating system on first launch, and you can change it later in the settings dialog (or with --lang on the command line).
The rest of this site, the detailed documentation, the license agreement and the contact form are available in Japanese only. This page is the English summary of them. If that is a problem for you, please let me know through thecontact form (in Japanese) — written English is welcome even though the form itself is not translated.
Hogandiff is developed by one person (nmby) in Japan. The Japanese pages carry the full documentation: product overview (in Japanese),how to use it (in Japanese) andrelease notes (in Japanese).