Before you commit, it's important to understand the trade-offs. The Benefits:

Open the , type cmd , right-click it, and Run as Administrator .

Compressing your C: drive feels like a hacker’s magic trick—freeing up tens of gigabytes with a single checkbox. But after running this on three different systems (an old HDD laptop, a modern SSD desktop, and a budget tablet), I’ve concluded that for the average user, it’s a net negative. You sacrifice performance, stability, and peace of mind for storage you probably don’t need to save.

If you are running Windows 10 or 11, you can use a more modern "CompactOS" feature. This specifically compresses operating system files, which can save several gigabytes without impacting general performance as much as full drive compression.

Note: This process can take anywhere from minutes to hours depending on your drive size and CPU speed. 2. Using the CompactOS Command (Advanced)