Convert JPG to WebP

What you actually gain

For the same perceived quality, WebP typically produces a file 25 to 35 per cent smaller than JPEG. The gap widens as the budget tightens: at generous sizes the two formats are close, but at aggressive targets WebP holds on to detail JPEG has already lost.

That is why FileBelow offers the switch specifically when you have set a tight size limit. After producing a JPEG it measures what WebP would achieve for your particular image at the same target, and only suggests the change when the difference is genuinely worth a click. It never changes format on you silently.

The re-encoding caveat

Converting a JPEG to WebP means decoding one lossy file and encoding it again in a different lossy format. The artefacts already present in the JPEG are treated as real detail by the WebP encoder and faithfully preserved, so you cannot recover anything the JPEG threw away, and a small amount of additional loss is unavoidable.

In practice, at a sensible quality, this is invisible. But it does mean the ideal workflow is to produce WebP from an original image rather than from a JPEG that has already been compressed hard. If you still have the original, start there.

Before you switch

WebP is universally supported by browsers, so for images on a website this is close to free performance. For anything being uploaded to a form, check that WebP is on the accepted list first — plenty of forms still specify JPG or PNG only, and will reject the file without explaining why.

If you are converting for a website and want to be careful, the usual approach is to serve WebP with a JPEG fallback inside a <picture> element, so older software still receives something it understands.