WebP is now supported by every major browser, which makes it excellent for websites. It can be smaller than JPG for photos and smaller than PNG for graphics with transparency. The problem is that browsers are not the only place images live. Many upload forms, email clients, document editors, print shops and older desktop apps still expect JPG or PNG.
That is why WebP to JPG remains one of the most useful everyday conversions. You are not converting because JPG is technically better. You are converting because JPG is accepted almost everywhere. Compatibility is sometimes more valuable than a slightly smaller file.
Convert when the destination rejects WebP
Convert WebP to JPG when a job application portal, government form, marketplace listing, school system or print service refuses the file. Also convert when you need to attach an image to an email thread where recipients may open it in old software. JPG is the least surprising option for people outside web development.
Do not convert WebP to JPG just because you want a smaller website image. In many cases the WebP is already smaller. Converting it to JPG may increase file size and remove transparency. If the image already works in its destination, keeping WebP is usually the better choice.
Watch transparency and quality
JPG cannot store transparency. If the WebP has transparent pixels, the converted JPG needs a background color. Many tools flatten transparency to white. That is fine for product photos on white pages, but wrong for logos or stickers that need to sit on different backgrounds. In those cases, convert WebP to PNG instead.
For regular photos, use a high JPG quality setting if the WebP has already been compressed. You are re-encoding an already compressed image, so extremely low quality settings can stack artifacts. A quality range around 85 to 90 is a safe starting point for photos you need to share or submit.