css - How to convert an image to retina display? -


i have 40px 20px image 72 pixels / inch.

i create retina display version.

what should do? double size? change resolution?

and in format should save it? png? jpg? ...

i using image on web site ...

in image editor, double size of image 80px 40px.

in markup set width 40 , height 20.

<img src="example.png" width="40" height="20" />

you should save png if need transparency or image line art. save photographs jpg.


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