Frequently asked questions

A free diff and 3-way merge tool for Windows. It compares text files side by side with word-level highlighting, compares whole folders, shows binary files byte by byte in a hex view, and resolves merge conflicts with an editable result pane. It is built to plug into TortoiseGit and git.

Yes. DiffScope is freeware: free to download and use, with no trial period, no licence key, no account and no nag screens. It is not open source, and all rights are reserved. The DiffScope Freeware License has the full terms.

No. The source code is not published. DiffScope is free to use, but copying it to other people, modifying it or reverse engineering it is not allowed (see the license). The third-party components it ships with, Electron and Chromium, keep their own open-source licences.

Windows 10 or 11, 64-bit (x64). The download is a portable zip of about 150.8 MB. No installer and no admin rights are needed.

Not yet. Version 1.0 is a portable zip for Windows 10/11 x64 only. Planned work is listed on the roadmap, and new releases appear in the changelog.

DiffScope is built with Electron, which bundles its own copy of the Chromium runtime. That runtime makes up most of the 150.8 MB. The upside is that DiffScope does not depend on anything else being installed on your PC.

1. Download DiffScope-1.0.1-win-x64.zip from the download page.
2. Right-click the zip and choose Extract All, to any folder you like (for example %LOCALAPPDATA%\Programs\DiffScope).
3. Run DiffScope.exe from the extracted folder.

Nothing is written to Program Files or the registry. To set it up as your diff and merge tool, follow TortoiseGit & git.

Yes. DiffScope.exe is not code-signed yet, so Microsoft Defender SmartScreen warns about it. Click More info › Run anyway. If you want to be sure the file is the one we published, check its SHA-256 first (next question). More background is on the security page.

Open PowerShell or Command Prompt in the folder you downloaded to and run one of these:

Get-FileHash .\DiffScope-1.0.1-win-x64.zip -Algorithm SHA256

certutil -hashfile DiffScope-1.0.1-win-x64.zip SHA256

The result must match this SHA-256 exactly (upper or lower case does not matter):

ee57ff27e5a2ee1db9b45608ddc4c4f476599f63d7232be61a462b28528688ff

DiffScope has no automatic updater, because it never connects to the internet. When a new version is listed in the changelog, download the new zip, close DiffScope and replace the old folder with the new one. Your settings live separately in %APPDATA%\DiffScope, so they are kept. If you extracted the new version to a different folder, update the exe path in TortoiseGit or your git config.

Yes, the extracted folder runs from anywhere. Settings are still stored per Windows user in %APPDATA%\DiffScope on each PC you use it on.

Please send them a link to the download page instead. The license lets everyone download and use DiffScope for free, but does not allow redistributing copies. Linking also means everyone gets the current version and can check its SHA-256.

Delete the DiffScope folder. To remove your settings too, delete %APPDATA%\DiffScope. If you set DiffScope up in TortoiseGit or git, switch those settings back to your previous tools (see TortoiseGit & git).

• Text files, side by side with line and word-level highlighting. See Text compare.
• Three versions for a merge (base, mine, theirs) with an editable result. See 3-way merge.
• Folders, recursively, by content, size or date, with exclude patterns.
• Binary files in a hex view, streamed so 100 MB+ files open quickly. See Folder & hex compare.

The right view opens automatically for what you give it.

No. DiffScope keeps UTF-8, UTF-16 and byte order marks as it found them, and CRLF stays CRLF, so a save does not turn into a whole-file diff.

Text views are virtualised and stay smooth on files of around 200,000 lines. Binary files are streamed in the hex view, so files of 100 MB and more open without a stall.

Yes. The text compare has options to ignore whitespace, case and blank lines, so re-indents and formatting changes do not hide the real edits. The same options exist on the command line (-w, -i, -B); see the CLI reference.

The most used ones are F7 / Shift+F7 for the next and previous difference, Alt+→ / Alt+← to copy a block across and Ctrl+S to save. The full list is in Keyboard shortcuts.

Yes. --headless runs without a window: it prints a unified diff, or writes a merge result with conflict markers, and returns an exit code (0 = identical or merged cleanly, 1 = different or conflicts left, 2 = error).

DiffScope.exe --headless old\app.js new\app.js > changes.diff

Every option is in the CLI reference.

For diff and merge, usually yes. It accepts the TortoiseGit and Beyond Compare switches (/base: /mine: /theirs: /merged: /title1:, read-only flags) and Beyond Compare’s four-argument merge order mine theirs base merged. Change the exe path and keep the rest.

In TortoiseGit Settings, point Diff Viewer and Merge Tool at DiffScope.exe with the parameters shown in TortoiseGit & git. The page has copy-paste command lines for both.

Add a difftool.diffscope and a mergetool.diffscope entry to your git config, then run git difftool or git mergetool. git difftool -d opens a whole-folder compare. The exact git config commands are in TortoiseGit & git.

The merge window exits with 0 only after you save with no conflicts left, and with 1 if you cancel or leave conflicts. Set mergetool.diffscope.trustExitCode = true so git relies on that instead of just checking whether the file changed. More on merging is in 3-way merge.

Put double quotes around every path that may contain spaces, including the path to DiffScope.exe itself, for example "C:\Program Files\DiffScope\DiffScope.exe" "%base" "%mine". In a git config, the quotes have to be escaped inside the cmd string; the integration guide shows the exact form.

No. The desktop app has no telemetry, no analytics, no crash reporter and no account. Your files never leave your computer. Details are in the privacy policy.

No. The app makes no network connections at all: no update checks, no licence checks, no crash uploads. It works fully offline, including on air-gapped machines.

It counts page views and downloads without cookies. For each one it records the page or file, the date, the approximate country and city, the operating system and browser family, the site that linked to you and a daily-changing pseudonymous visitor code. It does not store your IP address. The privacy policy lists every field.

A code-signing certificate is not in place yet. Until it is, the published SHA-256 lets you confirm that your copy is exactly the file we released. See Security.

Please do not post it publicly. The security page explains what to include. A contact address is coming soon.