First, the definition
| unit | Full name | Explanation | Brief |
| px | pixel | Pixels | |
| pt | point | point | |
| ppi | pixel per inch | The number of pixels per inch | |
| dpi | dot per inch | Dots per inch | |
| dp | density-independent pixels | Device-independent pixels | |
| sp | scale-independent pixels | Zoom independent pixels |
Second, the conversion