JPEG to WebP — Troubleshooting

Worked example

A WebP that is larger than the JPEG, a rejected upload or visible banding each have a clear cause, and none need a second conversion.

A larger WebP means the source JPEG was compressed harder than the fixed 92 percent used here. The fix is not to convert again but to keep the original JPEG for that picture, or to run the original through the Compress tool with WebP selected and a quality near 75 to 80.

If an upload form says the file type is not allowed, the destination simply does not accept WebP. Keep the JPEG, and if you still need WebP for your own site, keep both files and serve each where it is supported. Do not rename .webp to .jpg, because the contents are still WebP and the system may refuse or misread it.

Banding in a sky or a studio backdrop comes from lossy compression of smooth gradients. Check whether the original JPEG already shows the steps. If it does, no setting here will remove them; use a cleaner original.

If files are missing from the list, the batch limit of 12 images or 48 MB was probably reached, or the type is not JPG, PNG or WebP. When a result goes missing near the end of a large batch, the 64 MB output limit was hit, so download the finished files and process the rest.

JPEG photograph

WebP photograph

Never fix a rejected WebP by renaming its extension; keep a real JPEG for places that do not accept WebP.