Progressive

Use the progressive transformation to control progressive JPEG encoding for a delivered image variant.

Overview

Progressive JPEGs can display in passes as they load. The benefit depends on the image, network conditions, and where the image appears. Use auto when you want Imgwire's encoder policy to choose the value.

Syntax

Field	Value
Canonical parameter	progressive
Accepted values	true, false, auto
Applies to	JPEG output

Example

https://cdn.imgwire.dev/{organization_id}/{environment_id}/{image_id}?format=jpg&progressive=auto

image.url({
  format: 'jpg',
  progressive: 'auto',
  quality: 'auto',
});

imgwire images url img_123 --format jpg --progressive auto --quality auto

Best practices

• Use auto unless your application has a specific JPEG delivery policy.
• Pair progressive JPEG decisions with quality and chroma_subsampling.
• Test real pages with production-like image sizes before standardizing on a value.

Common mistakes

• Expecting progressive to affect WebP, AVIF, PNG, or GIF output.
• Treating progressive encoding as a replacement for responsive image sizing.
• Changing progressive behavior without also measuring file size and page rendering.

Related pages

• Chroma Subsampling
• Quality
• Format

Last updated at: May 9, 2026