Selecting the JDK version the IDE will run under

All the products on all the supported platforms already have 64-bit JetBrains Runtime 21 bundled and it will be used by default to run the IDE. If you need to change the runtime to a different version, see below. Please note that all the current IDE versions require at least Java 17 version to run. Our IDEs will not run on the older Java versions like Java 8 or 11.

All platforms: download and install JetBrains Runtime via Choose Boot Java Runtime for the IDE action

1. Start the IDE, use Help | Find Action (Ctrl+Shift+A or Cmd+Shift+A on Mac), type "Choose Boot Java Runtime for the IDE", press Enter.
2. Select the version to install, the higher the number after b, the more recent is the version. It makes sense to install the most recent version or the version you were asked to try by JetBrains staff. Installing old runtime versions may render your IDE unusable or introduce new issues.
3. Click the OK button and wait until the file with JetBrains Runtime is downloaded and configured.
4. Restart the IDE to try the new runtime.
5. Verify via About dialog that the new runtime is used. Notice the vendor (should be JetBrains s.r.o) and the release number (should correspond to the number after b in the file you've downloaded).
6. If the JDK version in the About dialog doesn't match or didn't change, see below. Most likely, you have an environment variable configured which has the priority over the <product>.jdk file. Remove any environment variables affecting IDE runtime selection and restart.

All platforms: Add Custom Runtime

1. Follow the steps from the section above to open the Choose Boot Java Runtime for the IDE dialog.
2. Use the Add Custom Runtime option
3. Select one of the already installed JDK 21 options or click Add JDK
4. To add a new JDK specify the home folder of the Java 21 installation on your disk

This option is useful to check if the issue you might have is specific to JetBrains Runtime or is common to this Java version from all the vendors. It helps to isolate and fix issues with JetBrains Runtime or workaround problems as you can continue working until the issue is resolved.

All platforms: Switch back to the default bundled JetBrains Runtime

1. Open the Choose Boot Java Runtime for the IDE dialog as described above
2. Click the Use Default Runtime button
3. Restart the IDE

If you can't start the IDE to access this dialog or the runtime doesn't change, please see below for the platform specific instructions. You would need to remove the <product>.jdk file from the configuration directory and unset any environment variables that override the default runtime. If there is no jbr subdirectory in the IDE installation directory, reinstall the product.

Windows

JDK (JetBrains Runtime) is bundled with all the product installers and it's recommended that you will use the provided JDK version unless there are any specific issues. Since 2017.1 version 64-bit JDK is bundled by default on all the systems.

<product>64.exe uses this JDK search sequence:

1. IDEA_JDK / PHPSTORM_JDK / WEBIDE_JDK / PYCHARM_JDK / RUBYMINE_JDK / CL_JDK / DATAGRIP_JDK / GOLAND_JDK environment variable
2. idea.config.path\<product>64.exe.jdk file
3. ..\jbr directory
4. system Registry
5. JDK_HOME environment variable
6. JAVA_HOME environment variable

c:\Program Files\Java\jdk17.0.10

Linux

• Starting from IntelliJ IDEA 2016 and the most recent versions of the lightweight IDEs, we are bundling custom JRE (JetBrains Runtime) with Linux distributions, just like we've been doing for Mac. Our custom JRE is based on OpenJDK and includes the most up to date fixes to provide better user experience on Linux (like font rendering improvements and HiDPI support).
• Boot JDK path is stored in the <product>.jdk file located in the config folder. It can be modified either via the Change IDE boot JDK action or by manually editing .jdk file (if you can't start the IDE to change it via an action).
• It's recommended to use the bundled JRE (if available). In case you have any issues with the bundled version, you can switch to the latest Oracle JDK or OpenJDK build available on your system (JDK 21 is recommended).
• Check bin/<product>.sh file for the JDK search order, it's similar to Windows in terms of the environment variable names. It's a legacy way to adjust the boot jdk, use it for older product versions. Consider using <product>.jdk file instead (see above), so that your modifications can survive IDE updates/re-installation.
• Check this answer if you need to install the JDK manually on Linux.
• If you have problems with ugly fonts, please see this thread comments for the tips.
• Help | About will show the actual JDK version.

macOS

• IDE is using the bundled JetBrains Runtime by default.
• If you override IDE JDK version (via the Choose Runtime plug-in), its path is stored in <product>.jdk file located in the config folder (idea.jdk for IntelliJ IDEA, pycharm.jdk for PyCharm, etc). Delete this file or change the path inside the file manually in case IDE no longer starts and you can't change it via the menu.
• If IDE doesn't start and this file doesn't exist, create it manually and specify Java path to use (Java home location), for example:
  /Library/Java/JavaVirtualMachines/jdk-21.jdk