Partitioning divides a single physical drive into separate logical volumes — useful for dual-booting, separating OS from data, or setting up a clean recovery partition. The process is straightforward in 2026 but still deserves a backup first. Here is the full guide for Windows, macOS, and Linux.
What changed in 2026
- GPT is now universal — virtually all systems sold since 2012 use UEFI and GPT. MBR is only relevant for legacy hardware or old external drives.
- Windows 11 Disk Management handles routine tasks cleanly; for resizing existing partitions that have free space in the middle of the disk, you still need a third-party tool like GParted.
- macOS Sonoma/Sequoia with APFS makes partition management more dynamic — APFS volumes share a container's free space automatically, which is better than fixed partition sizes.
- NVMe drives partition identically to SATA SSDs from the user perspective; the tools are the same.
GPT vs MBR — which to use
| Feature |
GPT |
MBR |
| Max drive size |
18 EB (effectively unlimited) |
2 TB |
| Max partitions |
128 (Windows), unlimited (Linux) |
4 primary |
| UEFI boot |
Yes |
No (BIOS only) |
| Modern OS support |
Required by Windows 11 |
Legacy only |
| Use case |
Everything from 2012 onward |
Old hardware, legacy drives |
Always use GPT unless you are dealing with a drive that must work on a machine from before 2010.
Partitioning on Windows 11
Using Disk Management (built-in):
- Press Win+X → Disk Management.
- Right-click the volume you want to shrink → Shrink Volume.
- Enter the amount to shrink in MB. Windows shows the maximum shrinkable space.
- Unallocated space appears. Right-click it → New Simple Volume.
- Follow the wizard: assign a drive letter, choose NTFS, format.
Limitations: Disk Management can only shrink to the point of immovable files (MFT, page file). If it gives less free space than expected, GParted from a live USB can do more.
Using diskpart (command line):
diskpart
list disk
select disk 0
list partition
select partition 3
shrink desired=51200
create partition primary
format fs=ntfs quick
assign letter=D
exit
Partitioning on macOS
Using Disk Utility:
- Open Disk Utility (Applications → Utilities).
- Select the physical drive in the sidebar (not a volume under it).
- Click Partition in the toolbar.
- Click the + button to add a partition.
- Set size, name, and format (APFS for macOS volumes; ExFAT for cross-platform).
- Click Apply.
For macOS, APFS containers are preferred over traditional partitions — multiple APFS volumes share a container's space dynamically. This is better than fixed partitions for macOS-only use.
Partitioning on Linux with GParted
GParted is the most capable GUI partition tool:
- Install:
sudo apt install gparted (or boot from a GParted Live USB for the OS drive).
- Select the drive from the dropdown (top right).
- Right-click a partition → Resize/Move to shrink it.
- Right-click the new unallocated space → New to create a partition.
- Choose filesystem: ext4 (Linux data), FAT32/exFAT (cross-platform), NTFS (Windows-readable).
- Click the green checkmark → Apply All Operations.
Command line with fdisk:
sudo fdisk /dev/sdb
g # create GPT
n # new partition
# accept defaults or specify start/end sector
w # write
sudo mkfs.ext4 /dev/sdb1
How to pick your partition layout
| Use case |
Suggested layout |
| Single-OS PC |
One partition for OS+data (simplest) |
| OS + separate data |
100–150 GB for OS, rest for data |
| Dual boot (Windows + Linux) |
Windows NTFS + Linux ext4 + shared exFAT |
| Media server |
OS partition (SSD) + data partition (HDD) |
Common mistakes
Not backing up first. Partition operations are mostly safe, but a power failure or bad sector during a resize can corrupt the filesystem. Back up anything important.
Shrinking a Windows partition that has a page file at the end. Move or disable the page file before shrinking, then re-enable it after.
Using MBR on a large new drive. MBR caps at 2 TB. A 4 TB drive formatted with MBR will show only 2 TB.
Leaving unallocated space by accident. After shrinking, create the new partition or the space sits wasted.
What to skip
- More than 3–4 partitions on a home PC — it adds complexity with no practical benefit. Folders do what most people hope extra partitions will do.
- FAT32 for large partitions — it caps files at 4 GB. Use exFAT for cross-platform drives or NTFS for Windows-primary.
- Partitioning an NVMe OS drive while Windows is running — use Windows Disk Management or GParted from a live USB instead.
FAQ
Will partitioning erase my data?
Creating a new partition in unallocated space does not erase existing data. Resizing an existing partition is also non-destructive if done correctly — but back up first.
Can I merge two partitions without losing data?
Only if you back up, delete one partition, extend the other into the freed space, then restore the backup. There is no lossless merge of two partitions directly.
How many partitions can I create on a GPT drive?
Windows supports up to 128. Linux has no practical limit. You will run out of reasons long before running out of partition slots.
What filesystem should I use for a drive shared between Windows and macOS?
exFAT — natively supported on both without drivers. NTFS is read-only on macOS by default (write requires third-party software or Microsoft's own NTFS for Mac).
Where to go next