The chances are that most of the photos on your website are in JPEG format, with logos and other flat artwork possibly in PNG. However, there are other formats around, and it’s worth knowing about them. One which I would draw attention to is WebP, which although rarely used, may be one to watch for the future. This is more of an advisory notice at the moment! Nothing ever stays the same on the web, and it’s good to keep up with developments.
The WebP format was acquired by Google several years ago, and is an open standard. It usually compresses images better than JPEG (sometimes substantially so) and this is of great interest to internet companies. Google itself says: “Images take up massive amounts of internet bandwidth because they often have large file sizes. According to the HTTP Archive, 60% of the data transferred to fetch a web page is images composed of JPEGs, PNGs and GIFs. Adding images to a page or making existing images larger have been proven to increase conversion rates. It’s unlikely that images will go away and so investing in an efficient compression strategy to minimize bloat becomes important.”
You can analyse the image sizes on the most important pages on your website here – if there seem to be substantial savings to be made, I’d seriously look into it.
When you do so, it’s quite possible that one of the site’s recommended alternative formats will be WebP. However, you can’t just re-save images in formats such as WebP, as they’re not supported by all browsers. You’d need to set up a ‘fall-back option’ of a supported format for those browsers, and that’s going to be too much work for most of us at the moment. Other options could be worth investigating though.