Shopify supports Image formats and its impact on site speed
In image format PNG is higher-quality whereas JPEG is smaller.if any image in your HTML on shopify should be a JPEG when possible (this will include product images).images that live in your css code should be PNG.
PNG images are produces better quality images,but comes with a larger file size.and use for:
2. JPEG or JPG
You may lose image quality, but you can adjust the quality level to find a good output.and use for:
banners or slideshows
pages and blog posts
Choose lossless or lossy compression using this,the only image format supported Browser:
Shopify automatically serves images in WebP format on supported browsers.