Why use WebP?
WebP is an image format designed for the web. It compresses photos more efficiently than JPG, so pages load faster, use less mobile data and score better in speed tests such as Google PageSpeed Insights. Every modern browser can show WebP images. Saving WebP needs Chrome, Edge or Firefox; Safari can display WebP but cannot create it yet, so on an iPhone or Mac choose JPG or use another browser.
For a website, combine conversion with resizing: an image displayed 1200 pixels wide does not need to be 4000 pixels wide. Doing both often cuts the file size by 90%.
When to keep JPG
Some older desktop software, printers and email programs still do not open WebP. If you are sending a photo to someone or attaching it to a document, JPG is the safer choice. Keep your originals and use WebP copies for the web.