How can I safely remove all my personal data from my PC before selling it?

One option is to just remove the hard drive altogether and sell the PC without it. You can keep the drive safe or use it later. It’s a simple solution if you want to ensure all your personal data stays with you.

You might want to look into doing a secure wipe of the hard drive before installing Windows. There are several tools out there that offer secure wiping options which can be more effective than the basic Windows tools, especially if you're concerned about data recovery by someone else.

Another quick tip is to just create a guest account. It won't remove your data, but it can limit what someone else can see immediately if you're loaning it out temporarily.

Encrypting the drive before formatting it is another solid plan. It adds a layer of security and practically prevents anyone from recovering your data. Just keep in mind that it will take some time to do.

If you want to be absolutely certain, the best method is to replace the drive entirely and physically destroy the old one. Most buyers won’t dig deep enough to recover data after a clean install unless they’re really determined.