Output image quality for lossy file formats.

The quality parameter enables control over the compression level for lossy file-formatted images.



value may be any integer between 1 and 100, where 1 is a lower quality image and a smaller file and 100 is the highest quality image and larger file. If desired, a second quality level can be specified for use when auto=webp is enabled and a WebP output format has been selected.


  1. The quality parameter can be applied to the following output formats: avif, jpg, pjpg, png8, webp and webply.
  2. If no quality parameter is present for jpg, pjpg, or webp, the output image will be returned at the default value set in the Image Optimizer web interface.
  3. If auto=webp is enabled by the URL or the service settings, the second value will be used as the quality value if the requestor sends the accept: image/webp request header.
  4. When only specifying quality, if the output image file size is larger than the input image, the original image will be delivered.
  5. This does not include a way of specifying auto AVIF quality.


Click the links to view the transformed image using a demo Fastly IO service.

Example usageDescription
?quality=85Output an image with quality set to 85.
?format=pjpg&auto=webp&quality=85,75Convert the image format to a progressive jpg with image quality set to 85. For browsers that support WebP set the image quality to 75.