Css for image url

Css for image url

The url() CSS function is used to include a file. The parameter is an absolute URL, a relative URL, a blob URL, or a data URL. 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 data type.

Note: There is a difference between a URI and a URL. A URI identifies a resource. A URL is a type of URI, and describes the location of a resource. A URI can be either a URL or a name (URN) of a resource.

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, whether a URL or a URN. Confusingly, this meant that url() could be used to create a CSS data type. This change was not only awkward but, debatably, unnecessary, since URNs are almost never used in actual CSS. To alleviate the confusion, CSS Level 3 returned to the narrower, initial definition. Now, url() denotes only true s.

/* 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/")  /* … */ > Experimental @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).

Syntax

Values

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

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:

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

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

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.

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HTML Images

Images can improve the design and the appearance of a web page.

Example

Example

Example

HTML Images Syntax

The HTML tag is used to embed an image in a web page.

Images are not technically inserted into a web page; images are linked to web pages. The tag creates a holding space for the referenced image.

The tag is empty, it contains attributes only, and does not have a closing tag.

The tag has two required attributes:

Syntax

The src Attribute

The required src attribute specifies the path (URL) to the image.

Note: When a web page loads, it is the browser, at that moment, that gets the image from a web server and inserts it into the page. Therefore, make sure that the image actually stays in the same spot in relation to the web page, otherwise your visitors will get a broken link icon. The broken link icon and the alt text are shown if the browser cannot find the image.

Example

The alt Attribute

The required alt attribute provides an alternate text for an image, if the user for some reason cannot view it (because of slow connection, an error in the src attribute, or if the user uses a screen reader).

The value of the alt attribute should describe the image:

Example

If a browser cannot find an image, it will display the value of the alt attribute:

Example

Tip: A screen reader is a software program that reads the HTML code, and allows the user to «listen» to the content. Screen readers are useful for people who are visually impaired or learning disabled.

Image Size — Width and Height

You can use the style attribute to specify the width and height of an image.

Example

Alternatively, you can use the width and height attributes:

Example

The width and height attributes always define the width and height of the image in pixels.

Note: Always specify the width and height of an image. If width and height are not specified, the web page might flicker while the image loads.

Width and Height, or Style?

The width , height , and style attributes are all valid in HTML.

However, we suggest using the style attribute. It prevents styles sheets from changing the size of images:

Example

Images in Another Folder

If you have your images in a sub-folder, you must include the folder name in the src attribute:

Example

Images on Another Server/Website

Some web sites point to an image on another server.

To point to an image on another server, you must specify an absolute (full) URL in the src attribute:

Example

Notes on external images: External images might be under copyright. If you do not get permission to use it, you may be in violation of copyright laws. In addition, you cannot control external images; they can suddenly be removed or changed.

Animated Images

HTML allows animated GIFs:

Example

Image as a Link

To use an image as a link, put the tag inside the tag:

Example

Image Floating

Use the CSS float property to let the image float to the right or to the left of a text:

Example

The image will float to the right of the text.

The image will float to the left of the text.

Tip: To learn more about CSS Float, read our CSS Float Tutorial.

Common Image Formats

Here are the most common image file types, which are supported in all browsers (Chrome, Edge, Firefox, Safari, Opera):

Abbreviation	File Format	File Extension
APNG	Animated Portable Network Graphics	.apng
GIF	Graphics Interchange Format	.gif
ICO	Microsoft Icon	.ico, .cur
JPEG	Joint Photographic Expert Group image	.jpg, .jpeg, .jfif, .pjpeg, .pjp
PNG	Portable Network Graphics	.png
SVG	Scalable Vector Graphics	.svg

Chapter Summary

• Use the HTML element to define an image
• Use the HTML src attribute to define the URL of the image
• Use the HTML alt attribute to define an alternate text for an image, if it cannot be displayed
• Use the HTML width and height attributes or the CSS width and height properties to define the size of the image
• Use the CSS float property to let the image float to the left or to the right

Note: Loading large images takes time, and can slow down your web page. Use images carefully.

HTML Exercises

HTML Image Tags

Tag	Description
	Defines an image
	Defines an image map
	Defines a clickable area inside an image map
	Defines a container for multiple image resources

For a complete list of all available HTML tags, visit our HTML Tag Reference.

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