The CSS background-image property sets an image as the background of an element. 1. Use background-image: url('image.jpg') to apply an image. 2. Combine with background-repeat to control tiling—use no-repeat for single images, repeat-x or repeat-y for directional tiling. 3. Apply background-size: cover or contain for responsive scaling. 4. Set background-position to adjust placement, like center for centered full-screen backgrounds. 5. Avoid using background-image for critical content images; use HTML img tags instead for accessibility and SEO. 6. Optimize large images for performance to reduce load times.
The background-image
property in CSS is used to set an image as the background of an element. Instead of using a solid color or gradient, you can use an image to fill the background area of a box — like a div, section, or even the whole page.

Setting a Background Image
To apply a background image, you simply use the background-image
property and point it to the image file using a URL. Here’s the basic syntax:
element { background-image: url('image.jpg'); }
This works for any block-level element. For example, if you want your entire webpage to have a background image, you might target the <body>
tag:

body { background-image: url('background.jpg'); }
You’ll usually also want to pair this with other properties like background-repeat
, background-size
, and background-position
to control how the image behaves across the screen.
Tiling and Repeating Images
By default, background images repeat both horizontally and vertically. This is useful if you're working with patterns or small textures that are meant to tile seamlessly.

If you don’t want the image to repeat at all — say, you’re using a large full-page banner — you can turn off repeating:
body { background-image: url('banner.jpg'); background-repeat: no-repeat; }
Or if you only want it to repeat vertically (like a vertical stripe), you can do:
background-repeat: repeat-y;
And likewise for horizontal repetition with repeat-x
.
- Use
no-repeat
for one-off images. - Use tiling when working with smaller patterned graphics.
- Be careful with large images — they can slow down your site.
Making It Responsive
One thing many developers overlook is making sure the background image scales nicely on different devices. You can control this with the background-size
property.
Here are some common values:
cover
: Scales the image so it always covers the entire element, cropping parts if needed.contain
: Scales the image so the whole thing fits inside the element, possibly leaving empty space.- Specific dimensions: Like
100% 100%
to stretch the image, or fixed sizes like300px 200px
.
For full-screen backgrounds that look good on all screen sizes:
body { background-image: url('landscape.jpg'); background-size: cover; background-position: center; }
This combination ensures the image fills the screen without distortion and centers itself.
When Not to Use It
While background images are powerful, they shouldn't be used for content-critical images — like logos or photos that carry meaning. Those should be added via HTML <img alt="What is the `background-image` property used for?" >
tags so they’re accessible, searchable, and indexable by search engines.
Also, keep performance in mind. Large background images can increase load time. Optimize them before use, and consider fallbacks for slower connections.
That's basically what the background-image
property is for — giving elements a visual layer behind the content. It’s simple to use but powerful when combined with other background-related properties.
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