Windows comes with its own defrag tool but here is a better one. Auslogics Disc Defrag Free.
I like this program because it does more for performance than just defrag:
You’ll have to turn on these settings but it’s not hard
- If set, this program will move your system files to the beginning of the hard drive for fast access to those frequently used files.
- Turn on scheduled and automatic defrag. This lets you set it and forget it.
- If set, this program will clear out temp files before defragmenting. No point in optimizing junk; get rid of it first.