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("https://mdn.mozillademos.org/files/16761/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('https://mdn.mozillademos.org/files/16761/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/") { ... }  
@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, list-style-image, content, cursor, border, border-image, border-image-source, mask, mask-image, src as part of a @font-face block, and @counter-style/symbol

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>

<url>

A url, which is a relative or absolute address, or pointer, to the web resource to be included, or a data uri, 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)

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(https://mdn.mozillademos.org/files/16761/star.gif);
}

Result

data-uri

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

.background {
  height: 100vh;
}

.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

Browser compatibility

See also

• <gradient>
• element()
• image()
• image-set()
• cross-fade()