University of Oregon

Creating a Partition in Mac OS X


Creating a Separate Data Partition During Installation
 OS X 10.5 and later 


  1. Open Disk Utility during installation.

  2. Select the hard drive you would like to partition and choose "Partition" in the main pane.

  3. Under "Volume Scheme," select the number of partitions you would like. Generally 2 will be sufficient.

  4. Select each partition and set a name for the volume and the format. For the operating system partition, it needs to be Mac OSX Extended (Journal). For your data partition, you can choose Mac OSX Extended (No Journaling)

  5. Change the size of the partitions by dragging the bar which divides them.

  6. Select the proper partition and install OSX.


Creating a Separate Data Partition In an Existing Copy of OS X


Navigate to Go > Utilities > Disk Utility.

  2. Select the hard drive you would like to partition.
Click 'Partition' in the main pane.
Select the '+' under the visual depiction of the drive. A new space for the partition will appear.

  5. Drag the bar separating the two partitions until the new partition is the size you would like it to be.

  6. Give it a name and choose a format if necessary.
Apply changes. Your main partition will be unchanged and merely resized and you will not lose personal data.