Since product images can come in all shapes and sizes, there’s no actual fixed size required. WooCommerce allows you to resize, crop and adjust the aspect ratio of your product images on the fly.
Navigate to Appearance > Customize > WooCommerce > Product Images to adjust the current size if needed. Once you update the size, WooCommerce will update the images automatically, feel free to change the values to try different sizes before publishing, use whatever size works best for your case.
