Resize your .mp3 cover art with Sanse Mp3 Art Sizer

1. Download Sanse Mp3 Art Sizer V 2.1 from archive.org (the original link isn’t available anymore).
2. Install the application.
3. Use the key combination WINDOWS + R to open the Run screen.
4. Type SanseMp3ArtSizer /500/90 to open Sanse Mp3 Art Sizer with the adjusted settings (/500 is for resizing the image to max 500 pixels, /90 is for the image quality)
5. Press Enter.

If you want to have your images smaller then 500×500 pixels, you can adjust this to your liking. By default the application is set to 250×250.