Background-Size

The background-size CSS property specifies the size of an element's background image. The image can be left to its natural size, stretched to a new size, or constrained to fit the available space while preserving its intrinsic proportions.

The demo above is interactive, edit values by selecting a container.

Example: Change background size: 30%; to 100%;

Values

contain

Scales the image as large as possible without cropping or stretching the image.

cover

Scales the image as large as possible without stretching the image. If the proportions of the image differ from the element, it is cropped either vertically or horizontally so that no empty space remains.

percentage

Stretches the image in the corresponding dimension to the specified percentage of the background positioning area.

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The background-size Values - Updated 1/4/2018