Yes, external hard drives can be partitioned. Partitioning allows you to divide the storage on your external hard drive into separate drives or volumes that function independently. This can be useful for organizing files more efficiently, keeping certain data separate, or running different operating systems on the same external drive.
What is partitioning?
Partitioning divides the available storage space on a drive into multiple logical sections called partitions. Partitions function as separate drives, with their own file systems and drive letters/mount points. They can be accessed independently from one another.
On Windows, drives are typically limited to 4 primary partitions. You can extend the number of partitions on a drive by creating logical partitions inside an extended partition. The total number of logical partitions is limited by the file system and available space.
On Macs, drives can be divided into as many partitions as needed, up to the total number of blocks available on the drive.
Partitioning does not physically split the drive into smaller devices. The partitions logical sections that are defined in the drive’s partition table. The data remains on one physical device.
Why partition an external hard drive?
There are a few reasons why you may want to partition an external hard drive:
- Organize files more efficiently – Partitioning allows you to separate different types of files, like documents, photos, music, etc.
- Keep data separate – You can keep personal and work files separate by storing them on different partitions.
- Run different operating systems – Partitioning lets you install and boot up different OS on the same drive, like Windows, Mac OS, Linux distributions.
- Isolate and limit data – You can restrict user or program access to a partition to protect sensitive files.
- Quickly format or erase partitions – Formatting one partition does not affect other partitions.
- Create backup images – Make an exact byte-for-byte copy image of a partition for backup or recovery purposes.
- Install multiple versions of programs – Some programs only allow one installation path per drive. Partitioning can help avoid conflicts.
- Increase manageability and organization – Partitions are easier to manage and navigate than a single large drive.
How to partition an external hard drive
Partitioning an external hard drive is a fairly straightforward process. The exact steps depend on your operating system and chosen partitioning tool.
On Windows
On Windows 10 and 11, the easiest way to partition an external drive is to use the Disk Management utility.
- Connect the external drive to your computer.
- Open the Windows search box and type “Disk Management”. Select the Create and format hard disk partitions result.
- Right-click the external drive listing and choose “Shrink Volume”. Enter the desired size for the new partition.
- Right-click the unallocated space created from shrinking and select “New Simple Volume”. Go through the wizard to format and assign a drive letter.
- Repeat to create additional partitions as needed.
You can also partition drives using the Windows DiskPart command line utility or third-party partitioning tools like MiniTool Partition Wizard, EaseUS Partition Master, AOMEI Partition Assistant, etc.
On Mac
To partition an external drive on Mac:
- Open Disk Utility, located in Applications > Utilities
- Select the external drive in the sidebar and click the Partition tab
- Click the Plus button to add a partition, then set the partition size and format
- Click Apply to create the partition
Repeat to create multiple partitions. You can also partition drives from Terminal using the diskutil command.
Using Third-Party Tools
There are many free third-party partitioning tools available for both Windows and Mac that provide more advanced partitioning options than the default utilities.
Some popular third-party partition managers include:
- EaseUS Partition Master
- MiniTool Partition Wizard
- AOMEI Partition Assistant
- Paragon Partition Manager
- GParted (for Linux and Mac)
These tools allow you to resize, move, copy, recover, and manipulate partitions with more flexibility. However, the built-in disk utilities are sufficient for basic partitioning in most cases.
Partition schemes
There are a couple options for how partitions are logically laid out on a drive, called partition schemes or partition styles:
MBR (Master Boot Record)
The Master Boot Record style is the older, legacy partitioning scheme originally used in DOS and early Windows operating systems. MBR has the following limitations:
- Supports up to 4 primary partitions per disk.
- Primary partitions can be extended into logical drives.
- Maximum of 2 TB partition size on larger hard drives. Smaller limit on bootable partitions.
- Requires an MBR boot sector on the drive’s first sector.
MBR is still used for compatibility with older systems, or when booting certain OS like Windows or Linux from UEFI/BIOS systems.
GPT (GUID Partition Table)
GPT is the newer partitioning method supported on newer 64-bit Windows, Mac OS, and Linux distributions running on UEFI. Advantages include:
- Supports unlimited number of partitions.
- Allows huge partition sizes over 2TB.
- Provides redundancy and cyclic redundancy checks (CRC) to better prevent errors.
- Defines partitions by unique identifiers called Globally Unique Identifiers (GUIDs).
GPT is required for drives larger than 2TB, and necessary for booting UEFI-based operating systems.
Partition alignment
For optimal performance, partitions should be aligned properly to the internal data blocks and erase blocks of the drive. Misaligned partitions can seriously degrade read/write speeds.
On SSDs, misalignments also cause more wear on the flash memory cells. Windows and Mac tools typically handle alignment automatically for best performance.
With Linux, you may need to manually align the partitions. Some tips:
- Use gdisk instead of fdisk, and choose optimal alignment when creating partitions.
- When specifying partition offsets, use alignment to 1024KiB blocks instead of cylinders.
- Make the start offset 1MiB for best SSD performance.
File system options
Partitions use file systems to organize and access the data on your drive. The file system defines how data is stored and retrieved. Some common file system options include:
NTFS
The NTFS (NT File System) is the modern Windows file system. It supports large partition sizes and modern security features like permissions and encryption:
- Compatible with all modern Windows OS
- Supports file sizes up to 16 EiB
- Allows security permissions for files and folders
- Supports disk quotas for user accounts and groups
- Allows data compression to optimize storage space
exFAT
exFAT is a lightweight file system optimized for external drives:
- Compatible with Mac and Windows
- Supports large partition sizes over 32GB
- Faster at writing lots of small files than NTFS
- No built-in security features
FAT32
FAT32 is an older file system supported across devices and operating systems:
- Compatible with all versions of Windows, Mac, Linux, game consoles, etc.
- Limited to 4GB maximum file sizes
- Limited to 8TB maximum partition size
- No built-in security features
- Higher chance of data corruption than NTFS
APFS
APFS (Apple File System) is the modern file system for Macs:
- Optimized and required for solid-state drives on modern macOS versions.
- Supports strong encryption and partitioning flexibility.
- Only readable on Mac devices.
HFS+
HFS+ (Hierarchical File System Plus) is the older Mac file system.
- Compatible with older Mac OS versions.
- Limited to 2TB partition sizes.
- Slower than APFS. Not recommended for external SSDs.
ext4
ext4 is the most widely used Linux file system:
- Works with all Linux distros and some other operating systems.
- Supports large partition sizes up to 1 EiB.
- Provides good overall performance.
Other file system options like ext2, ext3, XFS, Btrfs, and swap space are also available for Linux users and configurations.
Tips for partitioning external drives
Follow these tips when partitioning external hard drives:
- Back up any important data first before partitioning.
- Check the drive for errors to avoid data loss.
- Choose GPT if using UEFI or booting drives larger than 2TB.
- Leave at least 10-15% free space on any partitions you create.
- Make sure partitions are aligned properly for optimal performance.
- Use NTFS for shared Windows/Mac external drives.
- Use exFAT or FAT32 if you need wide compatibility.
- Don’t split drives used for backups into multiple partitions.
- Be careful when resizing partitions to avoid losing data.
Frequently asked questions
Is partitioning an external hard drive necessary?
Partitioning external drives is generally not required, but can be useful in many cases. A single partition works fine for basic external storage. But partitioning allows for more advanced drive configurations and management.
Can I resize or remove partitions later?
Yes, disk utility tools allow you to easily resize or delete partitions after creating them. Just be careful, as resizing can cause data loss if not done properly.
Can I use both MBR and GPT on one external drive?
No. A drive can use either MBR or GPT, but not both together. MBR is the older method, while GPT is newer and more capable.
How many partitions can I create on an external hard drive?
There is no single limit. For MBR, you can have up to 4 primary partitions, or 3 primary + 1 extended containing multiple logical drives. GPT has no set limit, but is based on available space.
Should I partition portable external HDDs or SSDs?
Partitioning portable external drives is generally not necessary, since the partition would just span the entire drive anyway. But you may partition portable drives to separate operating systems or types of files.
Can partitions on an external drive be encrypted?
Yes, many popular file systems like NTFS and APFS support setting passwords and enabling encryption on individual partitions. This allows sensitive data to be encrypted while keeping public data unencrypted.
How do I remove all partitions on an external drive?
Using the Windows Disk Management utility or Mac Disk Utility, you can delete all partitions on a drive to create one empty partition encompassing the full drive capacity. This will erase all existing data.
Conclusion
Partitioning external hard drives and SSDs can provide many benefits like organizing data, installing multiple operating systems, improving performance, and enhancing security.
Modern tools make it easy to create and manage partitions. Just be cautious when resizing and changing existing partitions, and be sure to align partitions properly for optimal performance.
With large high-capacity external drives, partitioning helps make better use of all that available storage space. And features like encryption and separate partitions for operating systems or personal and work files can improve privacy, productivity, and data protections.
