PyCharm 2017.1 Help

Tuning PyCharm

In this part:

Changing PyCharm properties

PyCharm makes it possible to change *.vmoptions and files without editing them in the PyCharm installation folder.

To create an empty file or to copy *.vmoptions file, choose the Help | Edit Custom Properties or Help | Edit Custom VM Options on the main menu respectively. Refer to the menu items description for details.

Managing *.vmoptions file

The location of the *.vmoptions file depends on the operating system you are currently using:

  • For Windows: <PyCharm installation folder>/bin/pycharm.exe.vmoptions or <PyCharm installation folder>/bin/pycharm64.exe.vmoptions
  • For *NIX: <PyCharm installation folder>/bin/pycharm.vmoptions or <PyCharm installation folder>/bin/pycharm64.vmoptions
  • For macOS, you need to make a copy of the pycharm.vmoptions file in the IDE preferences folder and then edit this copy. The reason is that the app bundle is signed and you should not modify any files inside the bundle.

    For older versions, the settings are stored in /Applications/PyCharm <version>.app/Contents/Info.plist.

To avoid editing files in the PyCharm installation folder, do one of the following:

  • From the main menu, choose Help | Edit Custom VM Options to create a copy of the pycharm.vmoptions file in the user home directory. Refer to Edit Custom VM Options for details.
  • Copy the existing file from the PyCharm installation folder somewhere and save the path to this location in the PYCHARM_VM_OPTIONS environment variable (IDEA64_VM_OPTIONS for 64 bit systems) .
  • Copy the existing <PyCharm installation folder>/bin/pycharm.exe.vmoptions or the <PyCharm installation folder>/bin/pycharm64.exe.vmoptions file from the PyCharm installation folder into your user home directory.

Then edit this file in the new location.

If the PYCHARM_VM_OPTIONS (IDEA64_VM_OPTIONS for 64 bit systems) environment variable is defined, or the *.vmoptions file exists, this file is used instead of the one located in the PyCharm installation folder.

Example: Increasing the heap size

To increase PyCharm heap size, you should copy the original pycharm.vmoptions file to the above-mentioned location, and then modify the -Xmx setting.

Managing file

The file located in the bin directory of the PyCharm installation folder should not be edited. Instead of editing the original file, create an file in the following location, open it for editing and add the required properties:

  • For Windows: %\USERPROFILE%\\.PyCharm XX
  • For *NIX: ~/.PyCharm XX
  • For macOS: ~/Library/Preferences/PyCharm XX

Example: Changing case of unicode literals

PyCharm allows defining whether non-ascii characters should use literals like '\u00AB' or '\00ab'.

This behavior is controlled by the system property idea.native2ascii.lowercase. By default, upper case characters are used.

If it is desirable to use lower case characters, create the file in the location specified above, open it for editing and add the following line:


Specifying custom JDK, properties or vmoptions files across platforms

A custom JDK, *.properties and *.vmoptions files are specified across platforms in a unified way.

All the launchers look at the following environment variables:


See Also

Last modified: 1 June 2017