You can calculate the PPI by following the link within this post:
Simple arithmetic:
- Divide the height in pixels by the height of the active area in millimeters, and you get 8.547008547 pixels per millimeter.
- Divide the width in pixels by the width of the active area in millimeters, and you get 8.547008547 pixels per millimeter.
There are 25.4 millimeters in an inch.
Therefore, the display has (8.547008547 pixels per millimeter) x (25.4 millimeters per inch) = 217 pixels per inch (217 PPI).