How to reduce or shrink a partition in windows 10?

If the disk management tool can't shrink a partition in windows 10, pls try the free diskpart tool instead.

In the command prompt, type:

diskpart

List all partitions in Windows 10.

list volume

This will display all existing partitions (volumes). Identify the volume number you want to shrink.

To shrink a partition by a specific amount (in megabytes), type:

shrink desired=XXXX

Replace XXXX with the amount (in MB) you want to shrink. For example, to shrink by 5000 MB (≈5 GB):

shrink desired=XXXX

Notes:

You can only shrink NTFS partitions using diskpart.

The shrinkable space depends on unmovable files. If there's not enough continuous free space, shrinking may fail or allow less than requested.

Use defrag and chkdsk before shrinking to improve success rate.