Diff Viewer

View and understand file changes with GitGUI's powerful diff viewer.

Opening Diffs

From Staging Panel

Click any file in the unstaged or staged sections.

From Commit Details

Click a commit, then click any file in the changed files list.

View Modes

Unified View

Traditional diff format with changes inline:

  context line (unchanged)
- removed line (red background)
+ added line (green background)
  context line (unchanged)

Best for:

• Quick scanning
• Small changes
• Familiar diff format

Split View

Side-by-side comparison:

Original (Left)	Modified (Right)
Old code	New code
Deletions highlighted	Additions highlighted

Best for:

• Large refactors
• Comparing structure
• Understanding rewrites

Toggle between views with the Unified / Split buttons.

Diff Features

Line Numbers

Both views show line numbers:

• Unified: Old line | New line columns
• Split: Each side has its own numbers

Syntax Highlighting

Code is colored based on file type:

• Keywords, strings, comments highlighted
• Makes code easier to read

Change Highlighting

• Green background — Added lines
• Red background — Removed lines
• No background — Context (unchanged)

Minimap

A vertical bar showing the entire file:

• Green marks = additions
• Red marks = deletions
• Click to jump to that section
• See change distribution at a glance

Scroll Sync (Split View)

In split view, both sides scroll together by default.

Toggle with the Sync / Free button:

• Sync — Scroll together
• Free — Scroll independently

Header Information

The diff header shows:

• File name and path
• Status badge — Staged or Unstaged
• View toggle — Unified / Split
• Action button — Stage or Unstage

Actions

Stage/Unstage

Click Stage File or Unstage File directly from the diff viewer.

Close

• Click the X button
• Press Escape

Understanding Diffs

Hunk Headers

@@ -10,5 +10,7 @@

Means: Starting at line 10, showing 5 old lines becoming 7 new lines.

Context Lines

Unchanged lines around changes help you understand location.

Binary Files

Images and other binary files show "Binary file" instead of a diff.

File Statuses

Status	Badge	Meaning
Modified	M	Content changed
Added	A	New file
Deleted	D	File removed
Renamed	R	File moved/renamed
Copied	C	File duplicated

Performance

Large diffs are handled efficiently:

• Virtual rendering for long files
• Smooth scrolling
• Minimap for navigation

Tips

Use the Minimap

For large files, the minimap shows where changes are concentrated.

Toggle Views

Switch between unified and split to get different perspectives.

Check Context

Look at surrounding code to understand the impact of changes.

Stage from Diff

You can stage/unstage directly without closing the diff viewer.

Keyboard Shortcuts

Shortcut	Action
Escape	Close diff viewer
Click file	Open that file's diff

Related

• Viewing Diffs Guide — Detailed usage
• Staging Panel — Managing files
• Commit Graph — Viewing history