AVIF and WebP are both modern formats that keep images small and handle transparency. WebP has been supported for longer, so it opens in more browsers, apps and upload forms. Converting AVIF to WebP is useful when a site or program accepts WebP but not AVIF.
Both formats are lossy, so converting from one to the other adds a second round of compression. Work from the best-quality AVIF you have and avoid converting the same image back and forth. WebP files are often a little larger than the AVIF they came from, since AVIF is usually the more efficient format. Your browser reads the AVIF, which works in current versions of Chrome, Firefox, Safari and Edge, so files may be skipped in older browsers.
Choose High for a good balance, Max for the least visible loss, or Low when file size matters most. The pixel dimensions follow the original, each file keeps its name with only the extension swapped, and no metadata or watermark is added. Everything runs in your browser, so your images are never uploaded.
Tip: if the place you are uploading to accepts neither, convert to JPG for photographs or PNG for graphics.
WebP is supported by more browsers, apps and upload forms. If something will not open your AVIF, WebP is a close alternative.
Often a little, because AVIF is usually the more efficient format. The difference depends on the picture.
Yes. Transparent areas of the AVIF stay transparent in the WebP.
Your browser has to be able to read AVIF, which current versions of Chrome, Firefox, Safari and Edge can. In an older browser the file cannot be decoded and is skipped.
Yes. Add them all, convert once and download a single ZIP. Only the extension changes. A file named holiday.avif becomes holiday.webp.
No. The conversion happens in your browser and the files never leave your device.