Set size on background image with CSS?

CSS2

If you need to make the image bigger, you must edit the image itself in an image editor.

If you use the img tag, you can change the size, but that would not give you the desired result if you need the image to be background for some other content (and it will not repeat itself like you seems to want)...

CSS3 unleash the powers

This is possible to do in CSS3 with background-size.

All modern browsers support this, so unless you need to support old browsers, this is the way to do it. Supported browsers: Mozilla Firefox 4.0+ (Gecko 2.0+), Microsoft Internet Explorer 9.0+, Opera 10.0+, Safari 4.1+ (webkit 532) and Chrome 3.0+.

.stretch{
/* Will stretch to specified width/height */
  background-size: 200px 150px;
}
.stretch-content{
/* Will stretch to width/height of element */
  background-size: 100% 100%;
}

.resize-width{
/* width: 150px, height: auto to retain aspect ratio */
  background-size: 150px Auto;
}
.resize-height{
/* height: 150px, width: auto to retain aspect ratio */
  background-size: Auto 150px;
}
.resize-fill-and-clip{ 
  /* Resize to fill and retain aspect ratio.
     Will cause clipping if aspect ratio of box is different from image. */ 
  background-size: cover;
}
.resize-best-fit{
/* Resize to best fit and retain aspect ratio.
   Will cause gap if aspect ratio of box is different from image. */ 
  background-size: contain;
}

In particular, I like the cover and contain values that gives us new power of control that we didn't have before.

Round

You can also use background-size: round that have a meaning in combination with repeat:

.resize-best-fit-in-repeat{
/* Resize to best fit in a whole number of times in x-direction */ 
  background-size: round auto; /* Height: auto is to keep aspect ratio */
  background-repeat: repeat;
}

This will adjust the image width so it fits a whole number of times in the background positioning area.

Additional note If the size you need is static pixel size, it is still smart to physically resize the actual image. This is both to improve quality of the resize (given that your image software does a better job than the browsers), and to save bandwidth if the original image is larger than what to display.

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Only CSS 3 supports that,

background-size: 200px 50px;

But I would edit the image itself, so that the user needs to load less, and it might look better than a shrunken image without antialiasing.

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If your users use only Opera 9.5+, Safari 3+, Internet Explorer 9+ and Firefox 3.6+ then the answer is yes. Otherwise, no.

The background-size property is part of CSS 3, but it won't work on most browsers.

For your purposes just make the actual image larger.

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Not possible. The background will always be as large as it can be, but you can stop it from repeating itself with background-repeat.

background-repeat: no-repeat;

Secondly, the background does not go into margin-area of a box, so if you want to have the background only be on the actual contents of a box, you can use margin instead of padding.

Thirdly, you can control where the background image starts. By default it's the top left corner of a box, but you can control that with background-position, like this:

background-position: center top;

or perhaps

background-position: 20px -14px;

Negative positioning is used a lot with CSS sprites.

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Not too hard, if you're not afraid of going a little more in depth :)

There's one forgotten argument:

background-size: contain;

This won't stretch your background-image as it would do with cover. It would stretch until the longer side reaches the width or height of the outer container and therefore preserving the image.

Edit: There's also -webkit-background-size and -moz-background-size.

The background-size property is supported in IE9+, Firefox 4+, Opera, Chrome, and Safari 5+.

^{- Source: W3 Schools}

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background-size: 200px 50px change it to 100% 100% and it will scale on the needs of the content tag like ul li or div... tried it

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In support of the answer that @tetra gave, I want to point out that if the image is an SVG, then resizing the actual image is not necessary.

Since an SVG file is just XML you can specify whatever size you want it to appear within the XML.

However, if you are using the same SVG image in different places and need it to be different sizes, then using background-size is very helpful. SVG files are inherently smaller than raster images anyway and resizing on the fly with CSS can be very helpful without any performance cost that I am aware of, and certainly little to no loss of quality.

Here is a quick example:

<div class="hasBackgroundImage">content</div>

.hasBackgroundImage
{
    background: transparent url('/image/background.svg') no-repeat 10px 5px;
    background-size: 1.4em;
}

(Note: this works for me in OS X 10.7 with Firefox 8, Safari 5.1, and Chrome 16.0.912.63)

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You totally can with CSS3:

body {
    background-image: url(images/bg-body.png); 
    background-size: 100%; /* size the background image at 100% like any responsive img tag */
    background-position: top center;
    background-repeat:no-repeat;
 }

This will size a background image to 100% of the width of the body element and will then re-size the background accordingly as the body element re-sizes for smaller resolutions.

Here is the example: http://www.sccc.premiumdw.com/examples/resize-background-images-with-css/

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Just have nested divs to be cross browser compatible

      <div>
         <div style="background: url('bg.gif') top repeat-y;min-width:490px;">
            Put content here
         </div>
      </div>
   

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You can use two <div> elements:

One is a container (it is the one which you originally wanted the background image to appear at).

The second one is contained within. You set its size to the size of the background image (or the size you wish to be appearing).

The contained div is then set to be positioned absolute. This way it does not interfere with the normal flow of items in the containing div.

It enables you to use sprite images efficiently.

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put the below code in the body of you css file

background-image: URL('../images/wave-green-plain-colour.jpg') ;
-webkit-background-size: cover;
-moz-background-size: cover;
-o-background-size: cover;
background-size: cover;
width:100px;

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You can't set the size of your background image with the current version of CSS (2.1).

You can only set: position, fix, image-url, repeat-mode, and color.

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You have written

background: url('bg.gif') top repeat-y;    
background-size: 490px;

but you will only see the background depending on the size of the container.

if you have an empty container with the background url and whatever the background-size is, you will not see the bg.gif.

If you set the size of the continer to

background: url('bg.gif') top repeat-y;    
background-size: 490px;
height: 490px;
width: 490px;

combined to the code you wrote above, you will be able to see the bg.gif file.

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background-size is working in Chrome 4.1, but so far I couldn't make it work in Firefox 3.6.

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I use background images for buttons, but it only shows the image the same size as the text, even if I set width and height. Instead, I pad out my text with   characters (non-breaking spaces). I slap in as many as needed, basically, until all the button background appears. So I might have code like this:

In the style sheet:

#v2menu-home {
    background-image:url(../v2-siteimages/button.png);
    background-repeat:no-repeat;
}

In the HTML document:

<div id="v2menu">
    <a id="v2menu-home" href="/index.php">home&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</a>
</div><!-- v2menu -->

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For example: Background image will always fit to container size (width 100% and height 100px). Cross-browser CSS:

.app-header {
background: url("themes/default/images/background.jpg") no-repeat;
-moz-background-size: 100% 100px;
-webkit-background-size: 100% 100px;
-o-background-size: 100% 100px;
filter: progid:DXImageTransform.Microsoft.AlphaImageLoader(src = "themes/default/images/background.jpg", sizingMethod = 'scale');
background-size: 100% 100px;

}

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This is possible to do in CSS3 with background-size

.backgroungImage {
    background: url('../imageS/background.jpg') no-repeat;
    background-size: 32px 32px;
}

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If you want to set background-size in the same background property you can use use:

background:url(my-bg.png) no-repeat top center / 50px 50px;

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