Product image too large on shop page

This doc will be of help:
https://docs.woothemes.com/document/using-the-appropriate-product-image-dimensions/

After changing the image size you’ll need to use the Regenerate Thumbnail plugin to resize them. Also, your theme may be resizing the image if it is responsive.

Thanks, Daniel – I had already done that. How do I tell if the theme is resizing the thumbnail? The images aren’t distorted, just cropped to 200×200.