To know the Java Bit version (64 or 32 Bit) you are using, you can use the command prompt

Java [-options] class [args]

-d32 use a 32-bit data model if available

-d64 use a 64-bit data model if available

Java command runs the .class file. It can take –d32 and –d64 as options.

To check whether a 64 bit data model is available, enter the command

Java –d64 -version

If it is not available you’ll get an error

Error: This java instance does not support a 64-bit JVM.

Please install the desired version.

If it is installed you’ll get the version.

Incase if you have 32 bit installed and in need of 64 bit. Install the 64 bit  jdk-7u45-windows-x64 from oracle. (x86 means 32 bit jdk-7u4-windows-i586)


In Netbeans IDE to change the bit version, go to projects window from window menu (shortcut : Ctrl+1).

Choose the project you want to build it using other version. Right click project and go to properties.

Images to change jvm required bit version

In project properties window choose Libraries and select Manage platforms.

manage platforms

The dropdown box shows current jdk data model (64 or 32 bit) and other jdk if available.

In java platform manager windows click on Add platform to add a new platform.

Browse the folder where you installed the required version and choose it. Give a name to the new platform and  click finish and close the window.

Now select the required java platform from drop down box and click OK.

The project will run using the given new java platform.