- MDPI: 48×48
- HDPI: 72×72
- XHDPI: 96×96
- XXHDPI: 144×144
- XXXHDPI: 192×192
to create an icon for different densities, you should follow the 2:3:4:6:8 scaling ratio between the five primary densities (medium, high, x-high, xx-high, and xxx-high respectively)
– developer.android.com