- The disk partition on Mac os x can allow you to manage both partitions in different ways. If you want to use another volume of the mac, it will require double space so, make a wise decision and select the right option according to the available space. It will give you a private space.
- MiniTool Partition Wizard Free. Supports lots of common disk partitioning tasks. Lets you extend.
Mac computers, whether you have an iMac, MacBook Pro, MacBook Air, or another Mac device, all have a finite amount of space. How you use it depends how quickly, or not, that space fills up and whether you need to add more space — either internally (such as upgrading to an SSD), or connecting to one or more external hard drives.
One thing you may not know is that the Mac boot drive is already partitioned. In all fairly recent models, the boot drive contains a secret partition that includes the macOS Recovery System, some essential Mac first aid tools and an installer, should, for any reason, your macOS fail to install or reboot.
Before we go into how to partition a Mac hard drive or SSD, let’s consider the benefits, and what you would need to do before partitioning a hard drive.
In a thread on Apple’s support forum, users complain that their Mac Disk Utility partition grayed-out while trying to partition their external hard drives. Probably, you just bought your external hard drive and are eager to use it on your Mac. But somehow, you cannot access the Mac Disk Utility partition, so you can’t write data to the drive.
Benefits of making a partition in a Mac hard drive
One of the main reasons for implementing a partition is to run more than one operating system, such as macOS on one and Windows on the other. Or you can run two versions of the same OS in both sides of the partition, all from a single disk. Each disk drive, with its own volume, is found and treat separately in the Finder.
Once you know how to partition a hard drive on Mac, or how to partition an external hard drive on Mac, you can format and manage them separately, effectively giving you two computers within one. Although, if you want to use the other volume to run an earlier version of your Mac — which you can, using Time Machine, the volume for that side has to be twice as large as the space it requires.
What to do before partitioning a hard drive
Before going ahead with a partition, it’s always useful to tidy your Mac up. Most users find they have way more clutter and junk than they think. Between old folders and documents, images and videos, apps taking up space, hundreds of email attachment downloads and local iOS backups, many people find they have at least 62GB of junk they simply don't need. We recommend downloading CleanMyMac X, a powerful Mac cleaner, ideal for decluttering your Mac before creating a partition.
How to partition a hard drive or SSD on Mac
There are several ways this can be done.
1. Use Boot Camp
Boot Camp is especially useful if you want to run Windows on your Mac. With Boot Camp comes Boot Camp Assistant, a handy app for partitioning your hard drive space so that one disk drive can run and operate macOS, and the other, Windows.
Disk Partition For Mac
Following the on-screen instructions of this Mac app, you can partition your hard drive or SSD space to ensure that Windows will run smoothly on your Mac, almost as if it was operating on a native Windows PC or other device.
However, for those who don't want to partition Mac for that purpose, you can use Disk Utility.
2. Use Disk Utility
Disk Utility is another Mac application that will repair and, as needed, partition disk drive spaces.
As a Mac partition manager, it is a useful app that sits within your Utilities folder, inside your Applications folder.
Before starting a Mac partition exercise, it’s worth fully backing-up the folder you want to copy using Carbon Copy Cloner. Another useful tool that gives you an instantly bootable copy of the drive you are going to partition, working on the assumption that if anything goes wrong during this process, you are going to lose everything that is on that hard drive. So with a backup, nothing can go wrong, and if it does, you can easily fix it.
Before partitioning:
- Clone the drive.
- Make sure the clone has worked and with your cloned drive you can boot this up from the startup menu.
- Plug the clone in and go to System Preferences > Startup Disk.
- Check the cloned drive works, and then you can partition without any worries.
Now you are ready to partition hard drive on Mac, starting with the following:
- Press Command-Shift-U or go to Utilities in the Applications folder.
- Double-click the Disk Utility application.
- In Disk Utility, select your Mac’s internal drive (or an internal SSD).
- You should see two options: First Aid or Partition.
- Click Partition.
- Click the ‘+’ below Partition Layout.
- Now a new Partition will appear, and you can change the size according to what you need.
- Give this new drive a name.
- If it hasn't worked exactly as you want, you can always click Revert to unpartition hard drive on Mac.
- Or, once you are happy with the size, click Apply. You may also be asked to click a lock symbol in the bottom left-hand corner to confirm everything.
How To Repartition In Windows 10
But don't worry if you want to make changes down the road. Everything you have done is reversible, so you can change the size or repartition hard drive on Mac.
Once the partition is done (which doesn't take as long as you might imagine) you will have a completely new hard drive or internal SSD, identical to your original, except without anything in it. Upload anything you need, or use the cloned version to store everything that was in the original hard drive - which still exists - in this partitioned version.
Within Disk Utility, you have the option of increasing or decreasing the size, erasing altogether (just remember to backup anything you need first), which will restore the space lost in the partition to your primary hard drive. Always backup before making any changes to a partition.
And remember, before making a partition, clean up your Mac from all the junk it contains. The fastest and the safest way to do that is to use CleanMyMac X. Try it today to rid your system of unwanted files and enjoy improved performance.
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Disk Utility User Guide
Partitioning a disk divides it into individual sections, each of which acts as a separate volume.
However, with APFS, you shouldn’t partition your disk in most cases. Instead, create multiple APFS volumes within a single partition. With the flexible space management provided by APFS, you can even install another version of macOS on an APFS volume.
Important: If you’re partitioning your internal physical disk because you want to install Windows, use Boot Camp Assistant instead. Do not use Disk Utility to remove a partition that was created using Boot Camp Assistant. Instead, use Boot Camp Assistant to remove the partition from your Mac.
Add a partition
Important: As a precaution, it’s best to back up your data before creating new partitions on your device.
In the Disk Utility app on your Mac, select a volume in the sidebar, click the Partition button , then click Partition.
Internal storage devices appear below the Internal section in the sidebar. External devices appear below the External section in the sidebar.
When you select a volume that already has data on it, the pie chart shows a shaded area representing the amount of data on the volume and an unshaded area representing the amount of free space available for another volume. Disk Utility also shows whether the volume can be removed or resized.
Note: If you see a small volume with an asterisk, the partition is smaller than can be represented at the correct scale in the chart.
Click the Add button .
Type a name for the volume in the Name field.
For MS-DOS (FAT) and ExFAT volumes, the maximum length for the volume name is 11 characters.
Click the Format pop-up menu, then choose a file system format.
Enter the size or drag the resize control to increase or decrease the size of the volume.
Click Apply, click Partition, then click Continue.
Click Show Details to view the step-by-step process of creating a new volume.
After the volumes are created, click Done.
After you partition a storage device, an icon for each volume appears in both the Disk Utility sidebar and the Finder sidebar.
Delete a partition
WARNING: When you delete a volume or partition, all the data on it is erased. Be sure to back up your data before you begin.
In the Disk Utility app on your Mac, select a volume in the sidebar, click the Partition button , then click Partition.
In the pie chart, click the partition you want to delete, then click the Delete button .
If the Delete button is dimmed, you can’t delete the selected partition.
Click Apply, then click Partition.
After the volume is deleted, click Done.
Erase a partition
In the Disk Utility app on your Mac, select the volume you want to erase in the sidebar.
Click the Erase button , then click Erase.
If the Erase button is dimmed, you can’t erase the selected volume.
After the volume is erased, click Done.
Enlarge a partition on a storage device
If you have multiple partitions on a device and one of them is running out of space, you may be able to enlarge it without losing any of the files on it.
To enlarge a volume, you must delete the volume that comes after it on the device, then move the end point of the volume you want to enlarge into the freed space. You can’t enlarge the last volume on a device.
WARNING: When you delete a volume or partition, all the data on it is erased. Be sure to back up your data before you begin.
In the Disk Utility app on your Mac, select a volume in the sidebar, then click the Partition button .
In the pie chart, select the partition you want to delete, then click the Delete button .
Click Apply.
The partition is removed, reformatted, and all free space is assigned to the previous partition.
Click Done.