About WinMerge Help

This is Help for WinMerge 2.16.

1. Audience and scope

WinMerge Help is intended for both new and experienced users. It explains how to use WinMerge, and documents its capabilities and limitations.

2. How to access Help

WinMerge Help topics are provided in two forms:

  • Microsoft HTML Help (WinMerge.chm), located in your WinMerge\Docs installation directory.

  • HTML manual on the WinMerge Web site.

You can access WinMerge Help in several ways:

WinMerge Help menu

While using WinMerge, click HelpWinMerge Help. HTML Help opens at the beginning (this topic).

Context-sensitive help

While using any WinMerge window, press F1. If a specific topic is available for your current window, Help opens at that topic. If not, Help opens at the beginning.

WinMerge command line

Use the /? or -? switch when running WinMerge from the command line. HTML Help opens at the beginning.

WinMerge Web site

Open your Web browser to winmerge.org. Under Documentation, follow the Manual link to the latest Help version.

3. How to use Help

Please read the following topics to learn essential WinMerge basics,

Quick start

Gets you quickly started with WinMerge and shows its basic usage.

Comparing and merging folders

Explains the folder comparison window, available operations, and customizing the results display.

Comparing and merging text files

Explains the file comparison/merge window, available operations, methods of navigation, and modes.

Comparing image files

Explains the image comparison/merge window.

Comparing in hexadecimal format

Explains the hex comparison/merge window.

Comparing in table format

Explains the table comparison/merge window.

Comparing Web pages

Explains the Web page comparison window.

Options and configuration

Explains how to customize WinMerge, including handling whitespace, colours, and text encoding.

To learn about WinMerge in more detail, read these topics:

Opening files and folders

Introduces several ways to open files and folders in WinMerge - there are many! For example, do you know how to use the Shell Extension context menu in advanced mode?


Describes the optional, extra features that you can add to WinMerge using its plugin mechanism.

Using Filters

Explains how to control what is compared in the folder or file comparison window.

Command line

Lists command-line parameters for using WinMerge with other tools or from a script.

Frequently asked questions

Contains answers to many common questions asked of developers.

Before submitting questions to GitHub, please check the Frequently asked questions topic first to see if your question is answered there.

4. Documentation conventions

Example Indicates
Enter UTF-8 in the field.

Click the Browse button to navigate to the path.

Press F5 once to refresh the window.

Bold font in descriptive text can indicate:
  • A value or string that you are instructed to enter

  • The name of a GUI button or keycap

Press Ctrl+O Press indicates a keyboard action. In this example, press the Ctrl and O keys in combination.

Click OK.

Click indicates a left mouse click on an object, such as a menu item or button.
Click FileOpen. The arrow indicates menu navigation. In the example, you choose the Open item in the WinMerge File menu .
Right-click the row and choose the Compare shortcut. Click the right mouse button on an object to open its context menu, and then either left-click or right-click the indicated item in the context menu.
Enter options file.ini

Use the Filter field to eliminate files from the operation.

One or more consecutive different lines form one difference (or diff).

Italicized text can represent:
  • A replaceable value or string. In the first example, you would substitute a real file name for the italicized term, but enter the ini file extension, which is not italicized, as written.

  • The name of a field, menu, or control in a WinMerge window.

  • A significant word or phrase that is introduced.

The path %WORKDIR%\project1 is expanded to C:\workfiles\project1.
Monospaced text can indicate:
  • A path or the name of a file or other system item

  • Sample code fragments

  • Sample output

  • Information that you enter in a form or on the command line

command inputpath [outputpath]

In syntax lines, brackets indicate optional elements. In this example, you must enter an input path with the command; you can enter an output path, but the command is valid without it.