This, of course, assumes that there's enough available free space on the drive to split things equitably. You can click the 'Divide Equally' button, which, as you might have guessed, will split your drive in half, using half of the available space for Mac OS X and half of the available space for Windows.

You may also notice that there are two predefined sizes to choose from, via the two buttons located just below the display of the partitions.

You'll also notice that you can't make the Windows partition smaller than 5 GB, although as we mentioned earlier, we don't recommend making it smaller than 20 GB. Use your mouse to click and drag the nub between the sections, to expand or shrink each partition, but don't click any of the buttons yet.Īs you drag the nub, you'll notice that you can only shrink the Mac OS X partition by the amount of free space that is available on the selected drive. The hard drive you selected in the previous step will display in Boot Camp Assistant, with one section labeled Mac OS X and the other labeled Windows. Click Done to complete your work here.įor more, get all you need to know about OS X El Capitan.Use the slider to divide the existing hard drive into two partitions, one for the existing OS X and one for Windows. Click the ' -' button and then click Apply.Īfter a minute or so, Disk Utility will finish applying changes to your drive and deem the operation successful. On the pie graph on the left, click the wedge that represents the partition you just erased. To do so, select your hard drive from the left panel and then click the Partition button at the top of Disk Utility. With the data erased from your partition, you still need to delete the now-empty partition in order to reallocate its space to the rest of your hard drive. This will bring up a window with an Erase button. With your partition selected, click the Erase button at the top of Disk Utility. Next, click on the partition that you want to delete in the left panel. To get started, open Disk Utility by searching for it using Spotlight or finding it in Applications > Utilities.

Partitioning mac hard drive