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image-resolution

Experimental: This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

The image-resolution CSS property specifies the intrinsic resolution of all raster images used in or on the element. It affects content images such as replaced elements and generated content, and decorative images such as background-image images.

The image resolution is defined as the number of image pixels per unit length, e.g., pixels per inch. By default, CSS assumes a resolution of one image pixel per CSS px unit; however, the image-resolution property allows a different resolution to be specified.

Syntax

image-resolution: from-image;
image-resolution: 300dpi;
image-resolution: from-image 300dpi;
image-resolution: 300dpi snap;

/* Global values */
image-resolution: inherit;
image-resolution: initial;
image-resolution: revert;
image-resolution: revert-layer;
image-resolution: unset;

Values

<resolution>: Specifies the intrinsic resolution explicitly.
from-image: Uses the intrinsic resolution as specified by the image format. If the image does not specify its own resolution, the explicitly specified resolution is used (if given), else it defaults to 1dppx (1 image pixel per CSS px unit).
snap: If the snap keyword is provided, the computed resolution is the specified resolution rounded to the nearest value that would map one image pixel to an integer number of device pixels. If the resolution is taken from the image, then the used intrinsic resolution is the image's native resolution similarly adjusted.

Note: As vector formats such as SVG do not have an intrinsic resolution, this property has no effect on vector images.

Formal definition

Initial value	`1dppx`
Applies to	all elements
Inherited	yes
Computed value	as specified, except with <resolution> possibly altered by computed for 'snap' value
Animation type	discrete

Formal syntax

image-resolution = 
  [ from-image || <resolution> ]  &&
  snap?

Examples

Setting a high dpi for print

When printing the document, use a higher resolution.

@media print {
  .myimage {
    image-resolution: 300dpi;
  }
}

Use image resolution with fallback

Uses the resolution from the image. If the image does not have a resolution, use 300dpi rather than the default 1dppx.

.myimage {
  image-resolution: from-image 300dpi;
}

Specifications

Specification
CSS Images Module Level 4 # the-image-resolution