Start WinMerge and either select Ctrl-O. The file/folder selection dialog opens:
from the -menu, or click the yellow folder icon on the toolbar, or pressTwo topmost fields in Open dialog are for selecting files and folders to compare. Comparison objects can be specified in one of four ways:
If Open-dialog Auto-completion -option is enabled in options WinMerge shows a list of paths available when typing into the fields. Auto-completion can be restricted to earlier used paths only, which makes selecting frequently used paths fast.
Folder can be selected from Windows Open dialog (opens when Filename field in Windows Open dialog contains text "Folder Selection" selecting button selects currently visible folder. Also if filename in Windows Open dialog does not match any real file parent folder is selected. Open dialog always shows backslash "\" at end of folder name.
-button is selected) by browsing into folder and selecting -button. It does not require selecting a file. When![]() |
Note |
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There can be only file & file or folder & folder selected to open for compare. If there is file & folder or other one of files/folders cannot be found WinMerge disables -button in dialog. |
Filter field can be used to select files by extension to compare. Default value is "*.*" which includes all files. But listing one or more extensions restricts compare to only files with those extensions. Multiple extensions are separated with space or semicolon. For example, entering the file filter *.cpp;*.hpp;*.c;*.h will cause WinMerge to ignore all files except C and C++ source files. You can only filter by file extension, not by filename.
File filters are a much more powerful way (than extension filters) to select files and folders. Use the Filters field to see a list of available filters, and to choose a file filter to use.
button next to theIf the Include Subfolders checkbox is checked then WinMerge compares all subfolders and shows all files and folders it finds in one view. Otherwise only the current folder is compared, and subfolders are listed by name (without their contents), so the user can browse into them.
Unpacker selection is for plugins.
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Tip |
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Status of currently selected files or folders is shown with text in bottom of the dialog. If one of the paths is invalid this text tells which one it is. |
Project files are the easiest and fastest way to open frequently used paths. Usually project files are opened using separate dialog accessible from Left- and Right-paths WinMerge compares selected project files. See Opening Files and Folders for more information about project files.
-menu. A project file can be also selected as left path in Open-dialog. Selecting project files toOpen-dialog is the main interface for opening files and folders. But WinMerge allows many other ways too:
If two folders were selected in the Open dialog then the folder compare window is opened. Folder compare is basically a list of found items. Found file- and folder-names are shown in rightmost column and other columns show other related information.
WinMerge does not have a concept of "original" and "changed" sides. WinMerge just shows what is different between two selected folders. This is especially the case for files and folders that are found only in other side. WinMerge does not show them as "added" or "removed" but unique items.
Using
menu items, toolbar items, or context menu items, files and folders can be managed in many ways. Most important action is making files and folders identical in both sides. This is done by selecting one of several Copy -items. When file or folder is copied to other side it becomes identical.If the selected file exists in both sides (and it is not a binary file) it can be opened to file compare. File can be opened by:
After file compare is closed file's status is updated to folder compare.
File compare shows two files side by side. Different lines are highlighted with background color. One or more consecutive different lines form one difference (or "diff"). WinMerge mostly works with these differences, not separate lines.
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Important |
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Notice how WinMerge fills missing lines in other side. Similar lines are always side by side. This is different from most other compare/merge programs and can take a while to learn. |
With merging commands (in
menu) lines in difference can be copied between sides. Missing lines can be copied also. When missing lines are copied from one side to another, matching existing lines are removed. In the above screenshot, copying lines in second difference from the left to the right would remove matching lines from the left side.WinMerge has an simple integrated editor. Typing, copying, cutting and pasting text works. If Automatic rescan is enabled then WinMerge updates file differences while files are edited. If Automatic rescan is disabled files can be updated selecting from -menu, clicking toolbar button with two yellow arrows or pressing F5 key.