PyCharm 2023.1 Help

Differences viewer for files

This dialog is displayed when you compare two files or two versions of a file (local changes or changes between local files and their revisions in a remote repository). You can compare files of any types, including binaries and .jar files. To open the dialog, select two files to compare or a file to compare its versions and press Control+D.

The differences viewer provides a powerful editor that enables code completion, live templates, and other features.

Diff & Merge viewer


Tooltip and Shortcut


the Previous Difference button/the Next Difference button

Previous Difference / Next Difference Shift+F7 F7

Jump to the next or previous difference.

When the last or the first difference is reached, PyCharm suggests clicking the arrow buttons or pressing F7/Shift+F7 once more and comparing other files modified locally. This behavior depends on the Go to the next file after reaching last change option in the Differences Viewer settings.

the Back button

the Forward button

Compare Previous/Next File


Compare the local copy of the previous or next file with its update from the server.

the Go To Changed File button

Go To Changed File Control+N

Display all changed files in the current change set and navigate to them. This action is only available when you review changes to multiple files.

the Jump to Source button

Jump to Source


Open the selected file in the editor. The caret is placed in the same position as in the Differences Viewer.


Select a viewer mode: side-by-side or unified. The side-by-side mode has two panels, the unified mode has one panel.

You can edit code and perform the Accept, Append, Revert actions in both viewers.

You can change text only in the right-hand part of the side-by-side viewer, or in the lower line in the unified viewer.

You can edit only local versions of your files. You cannot edit files that have read-only status.


Define how the differences viewer should treat whitespaces.

  • Do not ignore: white spaces are important, and all the differences are highlighted. This option is selected by default.

  • Trim whitespaces: trim whitespaces if they appear in the end and at the beginning of a line (("\t", " ")).

    • If two lines differ in trailing whitespaces only, these lines are considered equal.

    • If two lines are different, trailing whitespaces are not highlighted in the By word mode.

  • Ignore whitespaces: white spaces are not important, regardless of their location in the source code.

  • Ignore whitespaces and empty lines: ignores whitespaces and empty lines. The following entities are ignored:

    • all whitespaces (as in the 'Ignore whitespaces' option)

    • all added or removed lines consisting of whitespaces only

    • all changes consisting of splitting or joining lines without changes to non-whitespace parts.

      For example, differences between a b c and a \n b c are not highlighted in this mode.

Highlighting mode

Select the way differences granularity is highlighted.

The available options are:

  • Highlight words: modified words are highlighted

  • Highlight lines: modified lines are highlighted

  • Highlight split changes: if this option is selected, big changes are split into smaller changes.

    For example, A \n B and A X \n B X are treated as two changes instead of one.

  • Highlight symbols: modified symbols are highlighted

  • Do not highlight: if this option is selected, the differences are not highlighted at all.

    Use the Do not highlight option when you work with the files that were significantly modified. In such cases, highlighting might introduce additional difficulties during a review.

the Collapse All button

Collapse unchanged fragments

Collapse all the unchanged fragments in both files. The amount of non-collapsible unchanged lines is configurable in the Diff & Merge settings page. To open the Diff & Merge page, open settings by pressing Control+Alt+S and navigate to Tools | Diff & Merge.

the Synchronize button

Synchronize scrolling

Click this button to scroll both differences panes simultaneously. If this button is released, each of the panes can be scrolled independently.

the Settings button


Open a list of available settings.

These commands are also available from the context menu of the differences viewer gutter.

Include into commit Alt+I

This checkbox only appears if you invoke the Differences Viewer from the Commit Changes dialog with multiple changed files (all of which are deselected), and you explore the differences between them and hit the last difference in a file.

Select this checkbox if you want to include the file you've reviewed into the commit.

the Help icon



Open a browser and show the corresponding help page.


Switch between the panes of the differences viewer. The active pane has the cursor.

apply left apply right

Apply differences between panes (in case of the side-by-side viewer) or between lines (in case of the unified viewer).

The chevron buttons can change their behavior:

  • Click apply left and apply right to apply changes. This behavior is the default one.

  • Press Control to change apply left or apply right to chevron button bottom right or chevron button bottom left and append changes.

Merge actions

compare options button


Click this icon to invoke the list of options allowing you to compare different versions of a file to resolve a conflict.

Note that Base refers to the file version that the local and the repository versions originated from (initially displayed in the middle pane), while Middle refers to the resulting version.

the Apply Non-Conflicting Changes button

Apply All Non-Conflicting Changes

Click this button to apply all non-conflicting changes. You can also make this behavior automatic, by selecting the checkbox Automatically apply non-conflicting changes in the Diff & Merge page of the Settings dialog.

Apply Non-Conflicting Changes from the Left/Right

Apply Non-Conflicting Changes from the Left/Right Side

Click these buttons to merge non-conflicting changes from the left/right parts of the dialog.

Annotate with GitBlame

This option is only available from the context menu of the gutter.

Use this option to explore who introduced which changes to the repository version of the file, and when. The annotations view lets you see detailed information for each line of code, such as the version from which this line originated, the ID of the user who committed this line, and the commit date.

For more details on annotations, refer to VCS annotations.

Keyboard shortcuts

Keyboard shortcut


Use this keyboard shortcut to show the popup menu of the most commonly used diff commands.


Use this keyboard shortcut to switch between the left and the right panes.


Use this keyboard shortcut to undo/redo a merge operation. Conflicts will be kept in sync with the text.

Context menu commands

This context menu is available in the middle of the editor:




Select this check command to annotate the changes.

Show Whitespaces

Select this check command to show whitespaces as the dots in the Differences Viewer .

Show Line Numbers

Select this check command to show line numbers in the Differences Viewer.

Show Indent Guides

Select this check command to have PyCharm display vertical lines in the Differences Viewer to indicate positions of indents.

Use Soft Wraps

Select this check command to have PyCharm wrap the lines of code, when the dialog is resized.

Highlighting level

Use this menu item to select the highlighting level in the Differences Viewer. To learn more about the level of highlighting, refer to Change the highlighting level for a file.

This context menu is available in both editors:




Select this check command to annotate the changes.


Select these commands to accept or append the lines shown in the Differences Viewer.

Compare with Clipboard

Select this command to compare the file in the respective pane of the Differences Viewer with the contents of the Clipboard.

Switch to Three-Side Viewer

This option is available only when you are comparing two files against each other. It allows you to load a third file and add it to the comparison.

This context menu is available in the right-hand panel of the Differences Viewer:



Go to high-priority problems only/Go to next problem

Click one of these radio-buttons to define the way of navigating between the encountered problems.

Customize highlighting level

Click to show the slider to change the highlighting level in the Differences Viewer.

Show code lens on scrollbar hover

Enables viewing code outside of the visible area of the Differences Viewer when hovering the mouse over the scrollbar.

Productivity tips

Compare two SQL queries

You can compare contents in the clipboard with selected part of an SQL query.

  1. Copy an SQL query to the clipboard.

  2. Select and right-click the query in the editor with which you want to compare the query in the clipboard. Without selecting the query, you compare the clipboard contents with the whole file.

  3. From the context menu, select Compare with Clipboard.

Last modified: 16 August 2022