Filters

WinXMerge supports two types of filters to customize comparison behavior.

Line Filters

Exclude lines matching regex patterns from the comparison entirely. Useful for ignoring:

• Comments
• Timestamps
• Auto-generated content
• Version numbers

Configuration

1. Open Edit → Options… → Filters
2. Enter regex patterns separated by | (pipe)
3. Lines matching any pattern are excluded from the diff

Substitution Filters

Apply regex find/replace transformations before comparison. The original files are not modified — substitutions are applied only during diff computation.

Use cases:

• Normalize date formats
• Ignore version number differences
• Standardize whitespace

Configuration

1. Open Edit → Options… → Filters
2. Add substitution rules with a regex Find pattern and a Replace string
3. Multiple rules can be defined

Diff Options

In addition to filters, WinXMerge provides these comparison options (available in the toolbar as toggle buttons):

Option	Description
Ignore whitespace	Treat lines with different whitespace as equal
Ignore case	Case-insensitive comparison
Ignore blank lines	Skip empty lines
Ignore line endings	Ignore CR/LF differences
Moved line detection	Toggle detection of moved lines (blue highlight)

All settings are persisted across sessions.