Non-standard: This feature is non-standard and is not on a standards track. Do not use it on production sites facing the Web: it will not work for every user. There may also be large incompatibilities between implementations and the behavior may change in the future.

Deprecated: This feature is no longer recommended. Though some browsers might still support it, it may have already been removed from the relevant web standards, may be in the process of being dropped, or may only be kept for compatibility purposes. Avoid using it, and update existing code if possible; see the compatibility table at the bottom of this page to guide your decision. Be aware that this feature may cease to work at any time.

The -moz-device-pixel-ratio Gecko-only CSS media feature can be used to apply styles based on the number of device pixels per CSS pixel.

Warning: Do not use this feature. Use the resolution feature with the dppx unit instead.

Note: This media feature is also implemented by WebKit as -webkit-device-pixel-ratio. The min and max prefixes as implemented by Gecko are named min--moz-device-pixel-ratio and max--moz-device-pixel-ratio; but the same prefixes as implemented by Webkit are named -webkit-min-device-pixel-ratio and -webkit-max-device-pixel-ratio.



The number of device pixels per CSS pixel.

Media: @media Accepts min/max prefixes: yes


Basic compatibility example

-moz-device-pixel-ratio may be used for compatibility with Firefox older than 16, and alongside -webkit-device-pixel-ratio for compatibility with WebKit-based browsers that do not support dppx.


/* First, set for Webkit-based browsers */
@media (-webkit-min-device-pixel-ratio: 2),
  (min--moz-device-pixel-ratio: 2) /* Older Firefox browsers (prior to firefox 16) */,
  (min-resolution: 2dppx) /* The standard way */,
  (min-resolution: 192dpi); /* dppx fallback */

Note: See this CSSWG article for compatibility good practices regarding resolution and dppx.


Not part of any standard.

Browser compatibility

BCD tables only load in the browser

See also