guide · tortoisegit · tortoisesvn

Use Diffoniq as the diff viewer in TortoiseGit and TortoiseSVN

TortoiseGit and TortoiseSVN can hand every Diff to an external program. Point them at Diffoniq and a right-click on a changed file shows the stored revision next to your working file. The same line works in both clients, and it protects the side you should not edit.

1. Open the diff viewer setting

Client	Where
TortoiseGit	Settings → Diff Viewer → External
TortoiseSVN	Settings → External Programs → Diff Viewer → External

2. Enter this line

"C:\Program Files\Diffoniq\Diffoniq.exe" --read-only-left --no-backup %base %mine

That is the installer’s path; if you use the portable ZIP, put in the folder you unpacked it to. Then right-click a modified file and choose Diff: Diffoniq opens with the stored revision on the left and your working file on the right.

Why the two switches

When you compare a modified file against the repository, %base is a temporary copy of the stored revision, while %mine is your real working file. --read-only-left locks the temporary side; the title bar then says [Read-only: left]. Your working file on the right stays editable, and you can drag lines from the old version into it and save.

--no-backup matters the moment you save: Diffoniq normally keeps the original as a .BAK file next to it. Inside a working copy that would be a new, unversioned file that is easy to commit by accident — and the repository already keeps the old version for you.

Both switches apply to that one call only. They are never written to Diffoniq’s settings, so opening Diffoniq yourself still works as before.

Comparing two old revisions

If you compare two stored revisions with each other, both sides are temporary copies. Nothing is written back to the repository in that case, but edits would be thrown away with the copies. If you mostly work that way, use --read-only instead of --read-only-left in the line above; it locks both sides.

Good to know

Diff viewer only. Leave the merge tool setting as it is; Diffoniq is a diff viewer, not a merge tool.
Esc closes the comparison and brings you back to the client.
Using git on the command line as well? The same switches work for git difftool, including whole-folder comparisons.

The full reference is in the help: Version Control Clients and IDEs.

Try it in your own working copy

Diffoniq runs on Windows 10 and 11, 64-bit. Every feature is available for 30 days before you decide.

Try Diffoniq free for 30 days See pricing

TortoiseGit and TortoiseSVN are open-source projects of their respective developers. Diffoniq is not affiliated with either project.