How to reduce or shrink a partition in windows 10?

You can try a dedicated partition manager app if the following tricks did not work in Windows 11/10.

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.

There are several reasons why you can't shrink a partition in Windows 10, even if it looks like there is free space. Here's a breakdown of the most common causes.

1. Unmovable Files Are Blocking the Shrink

Some system files like the page file, hibernation file, or shadow copies—are marked as unmovable and located at the end of the volume. These block the shrinking operation because Windows can only shrink from the "end" of a volume.

You need to turn off system protection:

Go to Control Panel > System > System Protection > Configure and turn it off for the drive.

2. Insufficient Continuous Free Space

Even if you have 100 GB free, that space might be fragmented, and diskpart or Disk Management can't use non-contiguous space for shrinking.

To fix this, please run Disk Defragmenter (dfrgui) to consolidate free space.

3. Volume Is Not NTFS

Shrinking is only supported on NTFS partitions. If the volume is FAT32 or another file system, shrinking won’t be available.

Please convert the file system to NTFS with this commnad:

convert D: /fs:ntfs

Once it is fixed, you can now reduce the size of volume in Windows 10. or Windows 11.

How to shrink partition in Windows 10? Yeah, there's a definite risk when shrinking partitions in Windows 10.  It's not inherently dangerous like, say, plugging in a faulty USB drive, but it can go wrong if you're not careful.

My experience is that the biggest danger isn't the shrinking itself, but the what-ifs afterwards.  If you screw up the process, you could end up with a partition that's unusable, or worse, lose data.  It's easy to accidentally delete important files or mess up the allocation table, which is like the partition's instruction manual.

Think of it like this:  you're rearranging furniture in your house (the hard drive).  You're taking a room and making it smaller.  If you don't take out the things you want to keep in the new smaller room, you'll have a problem.  If you don't follow the instructions properly, you might end up with a room that's all jumbled up and nothing works right.

The most important thing is not how to shrink partition in Windows 10, but to back up you data. If you're not familiar with the process, don't attempt to shrink the partition yourself.  There are tools out there that might seem easier, but they can also cause issues.  It's best to leave it to someone who knows what they're doing or use the built-in tools carefully and methodically.

There are some things you need to pay attention to when shrink partition in Windows 10:

• File System: The file system on the partition (e.g., NTFS, FAT32) doesn't affect the shrinking process, but it does affect what you can do with the resulting unallocated space.
• System Partitions: Be extremely careful when shrinking partitions in Windows 10 that contain the operating system (Windows). Shrinking too much can render your system unusable. If you are unsure about the impact on system partitions, contact a technical support professional.
• Performance: Shrinking a partition can take some time, depending on the size of the partition and your computer's resources.
• Error Handling: If you encounter errors, carefully check the Disk Management tool to understand the reason. Don't proceed without understanding the error.
• Third-party tools: While Disk Management is the standard Windows method, third-party tools can offer more advanced options. Use them with extreme caution, as incorrect usage can lead to data loss.

Shrinking a partition in Windows 10 involves relocating the partition boundary, creating unallocated space. You must then either create a new partition out of that unallocated space or leave it as unallocated for other use.  Always backup your data and proceed cautiously.

Unfortunately, there's no built-in Windows 10 tool to directly shrink a partition Windows 10 in the way some might imagine, like a simple "shrink" button.  Windows 10's Disk Management utility can shrink a partition, but it does so by moving the partition boundary.  Any free space created at the end of a partition is not immediately usable.

The key is to understand that shrinking a partition involves relocating the partition boundary to create free space.  This free space is not immediately usable; it's a gap.  To be useful, you need to create a new partition out of it (or format and use it as unallocated space).

How to shrink partition in Windows 10:

1. Backup your data: This is crucial.  Any data on the partition you're shrinking could be lost if you make a mistake.

2. Open Disk Management:
Search for "disk management" in the Windows search bar.
Click on "Create and format hard disk partitions" (the Disk Management utility).

3. Identify the partition you want to shrink: Look for the partition you want to reduce in size.  Note its drive letter and size.

4. Right-click on the partition and select "Shrink Volume":

5. Specify the amount of space to shrink:  Disk Management will show the amount of space you can shrink.  Be cautious here.  Do not shrink more than necessary to avoid losing data.  If you're not sure, shrink a smaller amount.

6. Enter the amount you want to shrink (in MB):  Enter the desired amount of space to shrink and click "Shrink".

7. The system will shrink the partition:  This process takes some time.  Do not interrupt it.

8. You will see unallocated space at the end of the partition:

9.  Crucial Step: Don't format the unallocated space yet.  This is where many people make mistakes.  Formatting the unallocated space will erase any data.

10. (Optional but recommended) Create a new partition or extend an existing one:
    * Right-click on the unallocated space and select "New Simple Volume."
    * Follow the wizard to create a new partition (or optionally extend an existing one if you have another partition you want to grow).  If you just need free space, you can leave it as unallocated for now.