Css background image full size

Resizing background images with background-size

The background-size CSS property lets you resize the background image of an element, overriding the default behavior of tiling the image at its full size by specifying the width and/or height of the image. By doing so, you can scale the image upward or downward as desired.

Tiling a large image

Let’s consider a large image, a 2982×2808 Firefox logo image. We want (for some reason likely involving horrifyingly bad site design) to tile four copies of this image into a 300×300-pixel element. To do this, we can use a fixed background-size value of 150 pixels.

HTML

div class="tiledBackground">div> 

CSS

.tiledBackground  background-image: url(https://www.mozilla.org/media/img/logos/firefox/logo-quantum.9c5e96634f92.png); background-size: 150px; width: 300px; height: 300px; border: 2px solid; color: pink; > 

Result

Stretching an image

You can also specify both the horizontal and vertical sizes of the image, like this:

background-size: 300px 150px; 

The result looks like this:

Scaling an image up

On the other end of the spectrum, you can scale an image up in the background. Here we scale a 32×32 pixel favicon to 300×300 pixels:

.square2  background-image: url(favicon.png); background-size: 300px; width: 300px; height: 300px; border: 2px solid; text-shadow: white 0px 0px 2px; font-size: 16px; > 

As you can see, the CSS is actually essentially identical, save the name of the image file.

Special values: «contain» and «cover»

Besides values, the background-size CSS property offers two special size values, contain and cover . Let’s take a look at these.

contain

The contain value specifies that, regardless of the size of the containing box, the background image should be scaled so that each side is as large as possible while not exceeding the length of the corresponding side of the container. Try resizing the example below to see this in action.

HTML

div class="bgSizeContain"> p>Try resizing this element!p> div> 

CSS

.bgSizeContain  background-image: url(https://www.mozilla.org/media/img/logos/firefox/logo-quantum.9c5e96634f92.png); background-size: contain; width: 160px; height: 160px; border: 2px solid; color: pink; resize: both; overflow: scroll; > 

Result

cover

The cover value specifies that the background image should be sized so that it is as small as possible while ensuring that both dimensions are greater than or equal to the corresponding size of the container. Try resizing the example below to see this in action.

HTML

div class="bgSizeCover"> p>Try resizing this element!p> div> 

CSS

.bgSizeCover  background-image: url(https://www.mozilla.org/media/img/logos/firefox/logo-quantum.9c5e96634f92.png); background-size: cover; width: 160px; height: 160px; border: 2px solid; color: pink; resize: both; overflow: scroll; > 

Result

See also

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This page was last modified on May 24, 2023 by MDN contributors.

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CSS Background Image Size Tutorial – How to Code a Full Page Background Image

This tutorial will show you a simple way to code a full page background image using CSS. And you’ll also learn how to make that image responsive to your users’ screen size.

Making a background image fully stretch out to cover the entire browser viewport is a common task in web design. Fortunately, this task can be taken care of with a few lines of CSS.

Cover Viewport with Image

First, we will want to make sure our page actually covers the entire viewport:

Inside html , we will use the background-image property to set the image:

background-image: url(image.jpg); /*replace image.jpg with path to your image*/

Magic of ‘Background-Size’ Property

The magic happens with the background-size property:

cover tells the browser to make sure the image always covers the entire container, in this case html . The browser will cover the container even if it has to stretch the image or cut a little bit off the edges.

Because the browser may stretch the image, you should use a background image that has high enough resolution. Otherwise the image may appear pixelated.

If you care about having all of the image appear in the background, then you will want to make sure the image is relatively close in aspect ratio compared to the screen size.

How to Fine Tune an Image Position and Avoid Tiling

The browser can also choose to display your background image as tiles depending on its size. To prevent this from happening, use no-repeat :

background-repeat: no-repeat;

To keep things pretty, we will keep our image always centered:

background-position: center center;

This will center the image both horizontally and vertically at all times.

We have now produced a fully responsive image that will always cover the entire background:

How to Fix an Image in Place When Scrolling

Now, just in case you want to add text on top of the background image and that text overflows the current viewport, you may wish to make sure your image stay in the background when the user scrolls down to see the rest of the text:

background-attachment: fixed;

You can include all of the background properties described above using short notation:

background: url(image.jpg) center center cover no-repeat fixed;

Optional: How to Add a Media Query for Mobile

To add some icing on the cake, you may wish to add a media query for smaller screens:

@media only screen and (max-width: 767px) < html < background-image: url(smaller-image.jpg); >> 

You can use Photoshop or some other image editing software to downsize your original image to improve page load speed on mobile internet connections.

So now that you know the magic of creating a responsive, full page image background, it is time to go create some beautiful websites!

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How to Make HTML Background Image Full Screen?

It is often more visually pleasing and interesting to add images to the background of certain parts of a website than to change only the color of the background. Depending on the available space, the image can be left at its natural size, stretched, or constrained. This article describes how to set an image as the background for an element using the background-size property in CSS.

Pre-requisites

1. HTML for the structure of our image.
2. CSS for styling and making our background image responsive.

What are we Creating?

Here we’ll learn how to stretch a background image to cover the entire browser viewport. The CSS background-size property will be used to accomplish this, and JavaScript is not required. Background images are often stretched out to cover the entire browser viewport by web designers as it looks enticing to the users who are visiting our websites. It is pretty easy to accomplish this task by using a few lines of CSS in our projects. The final output of what we would create is shown below :

How to Make Full-Screen Responsive Background Image with CSS

To make our images responsive, we plan to do the following:

1. Fill the Entire Viewport with the background-size Property

It is possible to set the CSS background-size property to cover. Using this value, the browser will automatically and proportionally scale the background image’s width and height so that they are either equal to or greater than the view port’s width and height.

2. Use Media Queries to Provide a Smaller Background Image for Mobile Devices

A scaled-down version of the background image file will be served to speed up the page load on small screens with a media query. Choosing this option is optional.

What are the benefits of serving a smaller background image on a mobile device? In the demo, I used an image of about 5 9 7 6 ∗ 3 5 7 0 5976*3570 5 9 7 6 ∗ 3 5 7 0 px.

With this size, we’ll be covered on the vast majority of widescreen computer monitors currently available. However, it will require us to serve up a 1 . 5 M B 1.5MB 1 . 5 M B file.

It is never a good idea for a background photo to take up such a large amount of data, but it is especially bad for mobile Internet. Further, the image dimension is too large on small-screen devices.

We can make the images responsive by using the following approach:

Here is all the markup you need:

We will assign the image to be used as a background to the body element so that the image always covers the entire viewport of our browsers.

Now our background image covers the entire viewport of the browser, and we’re going to assign the image to the body element. Nevertheless, this technique works on any element at the block level (such as a div or a form).

The background image will always scale so that it covers the whole block-level container if the container’s width and height are fluid.

Here’s where the magic happens. Whenever this property/value pair is set, the browser scales the background image to conform to an element’s width and height. Here we’re using the body element as an example.

When a browser sees a background image that is smaller than the body element’s dimensions, it will programmatically enlarge the image. This happens on high-resolution screens with small background images.

It is well known that when images are scaled above their natural dimensions, the image quality degrades (pixelation occurs).

Image quality is negatively affected when images are scaled beyond their natural dimensions.

Consider that when selecting the image for your project, As the demo uses 5 9 7 6 ∗ 3 5 7 0 5976*3570 5 9 7 6 ∗ 3 5 7 0 px photos for larger screens, it’ll be a while before there are problems.

Depending on the size of your background image, the browser can display it as tiles.

Using no-repeat will prevent this from happening:

We will keep our image centered on keeping things looking nice:

In this way, the image will be vertically and horizontally centered at all times.

The next problem is when the height of the content is greater than the height of the visible viewport. In this case, there will be a scroll bar. The background image must remain in place during scrolling down. Otherwise, either the image runs out at the bottom of the background or moves when the user scrolls down (which can be very distracting).

This can be accomplished by setting the background-attachment property to fixed.

Using short notation, all of the background properties described above can be included :

Now we have achieved a fully responsive image that will always cover the entire background and look enticing to the users who visit our website. The code to achieve it is shown below :

The output with the usage of the media query is shown below :

If your mobile connection is slow, you can downsize your original image using Photoshop or another image-editing software.

One of the major disadvantages of using the media query is that, when the browser window is resized, for example, from 1 2 0 0 p x 1200px 1 2 0 0 p x to 6 4 0 p x 640px 6 4 0 p x (or vice versa), the background image will momentarily flicker while it loads.

HTML Background Image Full Screen Without CSS

A variety of methods can be used to set the HTML background image to full screen. In this example, the image will cover the entire screen. This can be done with or without CSS. As you can see in the example below, when we zoom in and out, there is no change in the background image, which is all done using the HTML attributes without adding any CSS.

1. The first property used here is a background image, which sets an image as the background by using the URL.
2. Background-repeat is the next attribute used to keep our image from repeating.
3. Background size is one of the most important attributes used here because it fixes the image in the background so that it does not change when the webpage is zoomed in and out. The cover is given as the value.

Conclusion

1. The CSS background-size property has been used to make the HTML background image full-screen.
2. An element’s background image is controlled by the background-size CSS property. Depending on the available space, the image can be left at its natural size, stretched, or constrained.
3. It is also possible to add an image without using CSS using the background-image, background-repeat, and background-size attributes.

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