url()

The url() CSS function is used to include a file. The parameter is an absolute URL, a relative URL, or a data URI. The url() function can be passed as a parameter of another CSS functions, like the attr() function. Depending on the property for which it is a value, the resource sought can be an image, font, or a stylesheet. The url() functional notation is the value for the <url> data type.

/* Simple usage */
url(https://example.com/images/myImg.jpg);
url(data:image/png;base64,iRxVB0…);
url(myFont.woff);
url(#IDofSVGpath);

/* associated properties */
background-image: url("star.gif");
list-style-image: url('../images/bullet.jpg');
content: url("pdficon.jpg");
cursor: url(mycursor.cur);
border-image-source: url(/media/diamonds.png);
src: url('fantasticfont.woff');
offset-path: url(#path);
mask-image: url("masks.svg#mask1");

/* Properties with fallbacks */
cursor: url(pointer.cur), pointer;

/* Associated short-hand properties */
background: url('star.gif') bottom right repeat-x blue;
border-image: url("/media/diamonds.png") 30 fill / 30px / 30px space;

/* As a parameter in another CSS function */
background-image: cross-fade(20% url(first.png), url(second.png));
mask-image: image(url(mask.png), skyblue, linear-gradient(rgba(0, 0, 0, 1.0), transparent);

/* as part of a non-shorthand multiple value */
content: url(star.svg) url(star.svg) url(star.svg) url(star.svg) url(star.svg);

/* at-rules */
@document url("https://www.example.com/") { ... } 
    Экспериментальная возможность

@import url("https://www.example.com/style.css");
@namespace url(http://www.w3.org/1999/xhtml);

Relative URLs, if used, are relative to the URL of the stylesheet (not to the URL of the web page).

The url() function can be included as a value for background, background-image, list-style (en-US), list-style-image, content, cursor, border, border-image (en-US), border-image-source, mask (en-US), mask-image (en-US), src (en-US) as part of a @font-face block, and @counter-style/symbol (en-US)

In CSS Level 1, the url() functional notation described only true URLs. In CSS Level 2, the definition of url() was extended to describe any URI, including URNs. CSS Values and Units Level 3 returned to the narrower, initial definition. Now, url() denotes only true <url>s.

Syntax

Values

<string>

A string which may specify a URL or the ID of an SVG shape.

<url>

A URL, which is a relative or absolute address, or pointer, to the web resource to be included, or a data URL, optionally in single or double quotes. Quotes are required if the URL includes parentheses, whitespace, or quotes, unless these characters are escaped, or if the address includes control characters above 0x7e. Double quotes cannot occur inside double quotes and single quotes cannot occur inside single quotes unless escaped. The following are all valid and equivalent:

<css_property>: url("https://example.com/image.png")
<css_property>: url('https://example.com/image.png')
<css_property>: url(https://example.com/image.png)

If you choose to write the URL without quotes, use a backslash (\) before any parentheses, whitespace characters, single quotes (') and double quotes (") that are part of the URL.

path

References the ID of an SVG shape — circle, ellipse, line, path, polygon, polyline, or rect — using the shape's geometry as the path.

<url-modifier>

In the future, the url() function may support specifying a modifier, an identifier or a functional notation, which alters the meaning of the URL string. This is not supported and not fully defined in the specification.

Formal syntax

url( <string> <url-modifier>* )

Examples

content property

HTML

<ul>
  <li>Item 1</li>
  <li>Item 2</li>
  <li>Item 3</li>
</ul>

CSS

li::after {
  content: ' - ' url(star.gif);
}

Result

data-uri

HTML

<div class="background"></div>

CSS

.background {
  background: yellow;
  background: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='90' height='45'%3E%3Cpath d='M10 10h60' stroke='%2300F' stroke-width='5'/%3E%3Cpath d='M10 20h60' stroke='%230F0' stroke-width='5'/%3E%3Cpath d='M10 30h60' stroke='red' stroke-width='5'/%3E%3C/svg%3E");
}

Specifications

Specification Status Comment
CSS Values and Units Module Level 4
Определение 'url()' в этой спецификации.		 Редакторский черновик
CSS Values and Units Module Level 3
Определение 'url()' в этой спецификации.		 Кандидат в рекомендации No significant change from CSS Level 2 (Revision 1).
CSS Level 2 (Revision 1)
Определение 'uri()' в этой спецификации.		 Рекомендация No significant change from CSS Level 1.
CSS Level 1
Определение 'url()' в этой спецификации.		 Рекомендация Initial definition.

Browser compatibility

BCD tables only load in the browser

See also