| City : | Quincy City |
| County : | Adams County |
| State : | Illinois (IL) |
| Land Area : | 15.91 sq mi |
| Water Area : | 0.04 sq mi |
| Latitude : | 39.9336751 |
| Longitude : | -91.3793040 |
| Population (2010): | 40,633 |
| Population Estimate (2012) : | 40,647 |
| Population Density : | 2,554.14/sq mi |
| Housing Units (2012) : | 18,655 |
| Median Household Income (2012) : | $41,239 (Illinois : $56,853, USA : $53,046) |
| Median Family Income (2012) : | $54,313 (Illinois : $70,144, USA : $64,585) |
| Median House Price (2012) : | $96,400 (Illinois : $190,800, USA : $181,400) |