Shrink a volume in Disk Management

What you will achieve

Reduce a partition’s size in Disk Management to free unallocated space — for dual-boot Linux, a new data partition, or expanding another volume later.

1) Open Disk Management

1. Press Win + X → Disk Management.
2. Or run diskmgmt.msc from Win + R.
3. Identify the volume to shrink — note file system (NTFS) and current size.

2) Suspend BitLocker if enabled

For encrypted system drives:

1. Open Settings → Privacy & security → Device encryption or search Manage BitLocker.
2. Click Suspend protection for the drive you will shrink.
3. Resume after resize completes.

3) Shrink the volume

1. Right-click the partition → Shrink Volume.
2. Wait while Windows queries shrinkable space — this can take minutes on large drives.
3. Enter the amount to shrink in MB (for example 51200 for ~50 GB).
4. Click Shrink. Unallocated space appears adjacent to the partition.

4) When shrinkable space is too small

Windows reports the maximum shrinkable size based on immovable files (pagefile, hibernation, restore points):

1. Run Disk Cleanup → Clean up system files.
2. Disable hibernation temporarily: Admin Command Prompt → powercfg /hibernate off
3. Delete old restore points or reduce System Restore disk usage.
4. Defrag HDDs only (not SSDs) via Optimise drives — helps consolidate free space on spinning disks.
5. Retry shrink in Disk Management.

5) Use the next unallocated space

Right-click unallocated space to New Simple Volume for a data partition, or leave it for Linux installer dual-boot. You cannot extend a different partition across an intervening volume without third-party tools or deleting partitions — plan layout before shrinking.

6) Shrink from command line

When Disk Management UI fails, Admin Command Prompt with diskpart:

diskpart
list volume
select volume C
shrink desired=51200
exit

desired= is megabytes. Check shrink querymax inside diskpart for the actual maximum before shrinking.

Related guides

• Partition disks during Windows setup
• CHKDSK — when and how