Quick answer: for images on a website, WebP is usually the better choice. It tends to produce smaller files than JPG at comparable visual quality and, unlike JPG, supports transparency. JPG is still the safer choice when the image has to open everywhere: email attachments, print services, older software and upload forms that only accept classic formats.

What is different about WebP

WebP was developed by Google and can store images in two ways: lossy compression (similar in purpose to JPG) and lossless compression (similar to PNG). It also supports transparency and animation, so one format can replace JPG, PNG and GIF in many situations.

Side-by-side comparison

  • File size. Google's own comparisons reported lossy WebP files roughly a quarter to a third smaller than JPG at equivalent quality. Treat that as a guide, not a promise: results vary with the image and the encoder settings, so test your own files.
  • Transparency. WebP supports it. JPG does not, so transparent areas become a solid colour, usually white.
  • Browser support. All current major browsers display WebP, including Chrome, Firefox, Edge and Safari (from 2020 onward).
  • Compatibility outside the browser. JPG opens in virtually every app, printer workflow and platform. WebP support is good in modern software but not universal, particularly in older editors and some upload forms.
  • Quality. Both are lossy when used for photos. Pushing either to a very low quality setting produces visible artefacts, just of different kinds.

Use WebP when

  • The image will be displayed on a web page and page weight matters.
  • You need transparency in a photo-like image and PNG would be too large.
  • You control where the file is used and know the viewers are modern browsers.

Use JPG when

  • You are sending the file by email, to a printer, or to someone whose software you do not know.
  • A form or marketplace only accepts JPG or PNG.
  • You want one file that works anywhere with no questions.

A practical approach

  1. Keep your original, highest-quality image.
  2. Compress a copy to WebP for the web and a copy to JPG for sharing.
  3. Compare the file sizes and look at both at full size before choosing. The Image Compressor shows the before and after, and the percentage saved, for either format.

Remember that dimensions matter as much as format. An image far larger than it is displayed wastes bytes in any format, so resize first with the Image Resizer. For how PNG fits in, see JPG vs PNG.