Diff tool support
Understand the diff tools that Unity supports, and how to set up a custom revision tool.
Read time 1 minuteLast updated 5 days ago
You can use the Revision Control Diff/Merge setting to set an installed diff tool as the default revision tool. You can also use this setting to define a custom revision tool with specific layouts.
If you want to change the diff tool that Unity uses, open the Preferences window, and navigate to the External Tools section. Select your preferred tool from the Revision Control Diff/Merge dropdown list.
Set up a custom revision tool
To set up a custom revision tool, follow these steps:
- Open the Preferences window, and navigate to the External Tools section.
- In the Revision Control Diff/Merge dropdown list, select Custom Tool.
- Enter the path to the custom tool's installation folder. On macOS, this should point to the folder in the tool's installation folder.
Contents/MacOS - Enter the arguments for two-way diffs, three-way diffs, and merges.
To specify file layout in the revision tool, use these arguments:
Property | Function |
|---|---|
| Left title |
| Right title |
| Ancestor title |
| Left file |
| Right file |
| Ancestor file |
| Output file |
| Absolute path to the left file |
| Absolute path to the right file |
| Absolute path to the ancestor file |
| Absolute path to the output file |
Examples:

SourceGear DiffMerge

P4Merge