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<image>

The <image> CSS data type represents a two-dimensional image.

Syntax

The <image> data type can be represented with any of the following:

  • An image denoted by the <url> data type
  • A <gradient> data type
  • A part of the webpage, defined by the element() function
  • An image, image fragment or solid patch of color, defined by the image() function
  • A blending of two or more images defined by the cross-fade() function.
  • A selection of images chosen based on resolution defined by the image-set() function.

Description

CSS can handle the following kinds of images:

  • Images with intrinsic dimensions (a natural size), like a JPEG, PNG, or other raster format.
  • Images with multiple intrinsic dimensions, existing in multiple versions inside a single file, like some .ico formats. (In this case, the intrinsic dimensions will be those of the image largest in area and the aspect ratio most similar to the containing box.)
  • Images with no intrinsic dimensions but with an intrinsic aspect ratio between its width and height, like an SVG or other vector format.
  • Images with neither intrinsic dimensions, nor an intrinsic aspect ratio, like a CSS gradient.

CSS determines an object's concrete size using (1) its intrinsic dimensions; (2) its specified size, defined by CSS properties like width, height, or background-size; and (3) its default size, determined by the kind of property the image is used with:

Kind of Object (CSS Property) Default object size
background-image The size of the element's background positioning area
list-style-image The size of a 1em character
border-image-source The size of the element's border image area
cursor The browser-defined size matching the usual cursor size on the client's system
mask-image ?
shape-outside ?
mask-border-source ?
symbols for @counter-style At risk feature. If supported, the browser-defined size matching the usual cursor size on the client's system
content for a pseudo-element (::after/::before) A 300px × 150px rectangle

The concrete object size is calculated using the following algorithm:

  • If the specified size defines both the width and the height, these values are used as the concrete object size.
  • If the specified size defines only the width or only the height, the missing value is determined using the intrinsic ratio, if there is any, the intrinsic dimensions if the specified value matches, or the default object size for that missing value.
  • If the specified size defines neither the width nor the height, the concrete object size is calculated so that it matches the intrinsic aspect ratio of the image but without exceeding the default object size in any dimension. If the image has no intrinsic aspect ratio, the intrinsic aspect ratio of the object it applies to is used; if this object has none, the missing width or height are taken from the default object size.
Note: Not all browsers support every type of image on every property. See the browser compatibility section for details.

Accessibility concerns

Browsers do not provide any special information on background images to assistive technology. This is important primarily for screen readers, as a screen reader will not announce its presence and therefore convey nothing to its users. If the image contains information critical to understanding the page's overall purpose, it is better to describe it semantically in the document.

Examples

Valid images

url(test.jpg)               /* A <url>, as long as test.jpg is an actual image */
linear-gradient(blue, red)  /* A <gradient> */
element(#realid)            /* A part of the webpage, referenced with the element() function,
                               if "realid" is an existing ID on the page */ 
image(ltr 'arrow.png#xywh=0,0,16,16', red) 
                            /* A section 16x16 section of <url>, starting from the top, left of the original
                               image as long as arrow.png is a supported image, otherwise a solid 
                               red swatch. If language is rtl, the image will be horizontally flipped. */ 
cross-fade(20% url(twenty.png), url(eighty.png)) 
                            /* cross faded images, with twenty being 20% opaque 
                               and eighty being 80% opaque. */ 
image-set('test.jpg' 1x, 'test-2x.jpg' 2x)  
                            /* a selection of images with varying resolutions */

Invalid images

nourl.jpg            /* An image file must be defined using the url() function. */
url(report.pdf)      /* A file pointed to by the url() function must be an image. */
element(#fakeid)     /* An element ID must be an existing ID on the page. */ 
image(z.jpg#xy=0,0)  /* The spatial fragment must be written in the format of xywh=#,#,#,# */
image-set('cat.jpg' 1x, 'dog.jpg' 1x) /* every image in an image set must have a different resolutions */

Specifications

Specification Status Comment
CSS Images Module Level 4
The definition of '<image>' in that specification.
Working Draft Adds element(), image(), image-set(), conic-gradient(), repeating-conic-gradient(), and image-resolution.
CSS Images Module Level 3
The definition of '<image>' in that specification.
Candidate Recommendation Initial definition. Before this, there was no explicitly defined <image> data type. Images could only be defined using the url() functional notation.

Browser compatibilityUpdate compatibility data on GitHub

Desktop
Chrome Edge Firefox Internet Explorer Opera Safari
<image> 1 12 1 10 2 1
cross-fade() 17
Prefixed
17
Prefixed
Prefixed Implemented with the vendor prefix: -webkit-
Supports the original dual-image with percentage implementation only.
79
Prefixed
79
Prefixed
Prefixed Implemented with the vendor prefix: -webkit-
Supports the original dual-image with percentage implementation only.
No No 15
Prefixed
15
Prefixed
Prefixed Implemented with the vendor prefix: -webkit-
Supports the original dual-image with percentage implementation only.
10
10
Supports the original dual-image with percentage implementation only.
5.1
Prefixed
Prefixed Implemented with the vendor prefix: -webkit-
Supports the original dual-image with percentage implementation only.
element() No No 57
Prefixed
57
Prefixed
Prefixed Implemented with the vendor prefix: -moz-
29 — 57
Prefixed
Prefixed Implemented with the vendor prefix: -moz-
-moz-element() is limited to background-image, background, border-image and border-image-source.
4 — 29
Prefixed
Prefixed Implemented with the vendor prefix: -moz-
-moz-element() is limited to background-image and background.
No No No
<gradient> 26
26
10
Prefixed
Prefixed Implemented with the vendor prefix: -webkit-
12
Prefixed
12
Prefixed
Prefixed Implemented with the vendor prefix: -ms-
3.6
3.6
Gradients are limited to background-image, border-image, and mask-image.
10
Prefixed
10
Prefixed
Prefixed Implemented with the vendor prefix: -ms-
12.1
12.1
11 — 15
Prefixed
Prefixed Implemented with the vendor prefix: -o-
15
Prefixed
Prefixed Implemented with the vendor prefix: -webkit-
6.1
6.1
5.1
Prefixed
Prefixed Implemented with the vendor prefix: -webkit-
image() No No No
No
The -moz-image-rect() function supports fragments as of Firefox 4.
No No No
image-set() 21
Prefixed
21
Prefixed
Prefixed Implemented with the vendor prefix: -webkit-
79
Prefixed
79
Prefixed
Prefixed Implemented with the vendor prefix: -webkit-
No
No
See bug 1107646.
No 15
Prefixed
15
Prefixed
Prefixed Implemented with the vendor prefix: -webkit-
6
Prefixed
6
Prefixed
Prefixed Implemented with the vendor prefix: -webkit-
Support for url images only and x is the only supported resolution unit. See bug 160934.
paint() 65 79 No No 52 No
Mobile
Android webview Chrome for Android Firefox for Android Opera for Android Safari on iOS Samsung Internet
<image> 1 18 4 11 1 1.0
cross-fade() ≤37
Prefixed
≤37
Prefixed
Prefixed Implemented with the vendor prefix: -webkit-
Supports the original dual-image with percentage implementation only.
18
Prefixed
18
Prefixed
Prefixed Implemented with the vendor prefix: -webkit-
Supports the original dual-image with percentage implementation only.
No 14
Prefixed
14
Prefixed
Prefixed Implemented with the vendor prefix: -webkit-
Supports the original dual-image with percentage implementation only.
9.3
9.3
Support for the original dual-image with percentage implementation only.
5
Prefixed
Prefixed Implemented with the vendor prefix: -webkit-
Supports the original dual-image with percentage implementation only.
1.0
Prefixed
1.0
Prefixed
Prefixed Implemented with the vendor prefix: -webkit-
Support for the original dual-image with percentage implementation only.
element() No No 60
Prefixed
60
Prefixed
Prefixed Implemented with the vendor prefix: -moz-
29 — 60
Prefixed
Prefixed Implemented with the vendor prefix: -moz-
-moz-element() is limited to background-image, background, border-image and border-image-source.
4 — 29
Prefixed
Prefixed Implemented with the vendor prefix: -moz-
-moz-element() is limited to background-image and background.
No No No
<gradient> ≤37
≤37
≤37
Prefixed
Prefixed Implemented with the vendor prefix: -webkit-
26
26
18
Prefixed
Prefixed Implemented with the vendor prefix: -webkit-
4
4
Gradients are limited to background-image, border-image, and mask-image.
12.1
12.1
11 — 14
Prefixed
Prefixed Implemented with the vendor prefix: -o-
14
Prefixed
Prefixed Implemented with the vendor prefix: -webkit-
7
7
6
Prefixed
Prefixed Implemented with the vendor prefix: -webkit-
1.5
1.5
1.0
Prefixed
Prefixed Implemented with the vendor prefix: -webkit-
image() No No No
No
The -moz-image-rect() function supports fragments as of Firefox 4.
No No No
image-set() 4.4
Prefixed
4.4
Prefixed
Prefixed Implemented with the vendor prefix: -webkit-
25
Prefixed
25
Prefixed
Prefixed Implemented with the vendor prefix: -webkit-
No
No
See bug 1107646.
14
Prefixed
14
Prefixed
Prefixed Implemented with the vendor prefix: -webkit-
6
Prefixed
6
Prefixed
Prefixed Implemented with the vendor prefix: -webkit-
Support for url images only and x is the only supported resolution unit. See bug 160934.
1.5
Prefixed
1.5
Prefixed
Prefixed Implemented with the vendor prefix: -webkit-
paint() 65 65 No 47 No 9.2

See also

© 2005–2020 Mozilla and individual contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/CSS/image