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CSS

Posted by Patrick Branham
Patrick Branham
2,341 Points

Device-pixel-ratio confusion

I don't understand how a device-pixel-ratio (DPR) of 1 is always equal to a ppi of 96. Assuming resolution is constant, wouldn't the ppi decrease as screen size increases, regardless of DPR?

1 Answer

John Kotz
John Kotz
8,591 Points

PPI is calculated with screen size and the number of pixels along the diagonal (pixels/inches), so as the screen size increases so to does the number of pixels. Whereas the DPR is a constant that can be used in conversions between metrics. DPR of 1 implies 96 ppi or 96 pixels in 1 inch of screen. DPR of 2 implies 192 pixels in 1 inch of screen and so forth.