How much smaller WebP gets
In our tests a 1280×575 landscape JPG of 221,419 bytes became 157,026 bytes as WebP at quality 80 (29% smaller) and 128,152 bytes at quality 75 (42% smaller). Google describes WebP as 25–34% smaller than JPG at comparable quality, which matches.
Push the quality too high and the saving disappears: the same photo at WebP quality 90 was 232,982 bytes, 5% larger than the JPG it came from. The row note warns you whenever the WebP ends up larger than the original.
Picking a quality for the web
- Photos on web pages: 75–82. Quality 80 is the default here.
- Images with text or fine lines: 90, because lower settings blur edges.
- Above about 85 the WebP loses most of its advantage over the original JPG; if you need that much quality, keep the JPG.
Converting a JPG is a second round of loss
A JPG has already been compressed with loss, and WebP compresses it again. Artifacts from both steps add up, so start from the camera original or a high-quality export when you can, and do not convert back and forth between JPG and WebP.
To check a result, open the original and the WebP side by side at 100% zoom and look at skies, skin and text — that is where extra blockiness or blur shows first.
Browser support and a fallback
WebP is supported by about 97% of browsers in use (caniuse), including Safari since version 16. For the rest, a picture element serves WebP where it works and the JPG elsewhere: <picture><source srcset="photo.webp" type="image/webp"><img src="photo.jpg" alt=""></picture>.
Content management systems such as WordPress accept WebP uploads, so you can often upload the converted files directly. Keep the JPG originals for email, print and older software.
Safari and iPhone cannot save WebP
Safari and every browser on iPhone and iPad can display WebP but cannot create it: asked for WebP, the canvas quietly returns PNG. This page detects that and tells you before converting instead of producing a mislabelled file.
On those devices, use a desktop browser such as Chrome, Edge or Firefox for WebP, or convert to JPG instead.
When the WebP is bigger or shows banding
- The WebP is bigger than the JPG: lower the quality to 75–80; very small or already heavily compressed JPGs may not shrink at all.
- Banding in skies or gradients: raise the quality to 85.
- The site still loads slowly: reduce pixel dimensions with Max width — a 4000 px photo in a 1200 px column wastes most of its bytes.