According to the United States Census Bureau, the city has a total area of 104.7 km² (40.4 mi²). 82.4 km² (31.8 mi²) of it is land and 22.2 km² (8.6 mi²) of it is water. The total area is 21.25% water.
As of the census of 2000, there are 48,208 people, 19,107 households, and 10,738 families residing in the city. The population density is 584.8/km² (1,514.6/mi²). There are 21,836 housing units at an average density of 264.9/km² (686.1/mi²). The racial makeup of the city is 56.35% White, 33.39% African American, 0.38% Native American, 0.98% Asian, 0.10% Pacific Islander, 5.69% from other races, and 3.11% from two or more races. 14.49% of the population are Hispanic or Latino of any race.
There are 19,107 households out of which 28.9% have children under the age of 18 living with them, 32.3% are married couples living together, 18.4% have a female householder with no husband present, and 43.8% are non-families. 33.8% of all households are made up of individuals and 12.5% have someone living alone who is 65 years of age or older. The average household size is 2.40 and the average family size is 3.10.
In the city the population is spread out with 26.3% under the age of 18, 11.4% from 18 to 24, 30.4% from 25 to 44, 17.6% from 45 to 64, and 14.3% who are 65 years of age or older. The median age is 32 years. For every 100 females there are 97.6 males. For every 100 females age 18 and over, there are 95.3 males.
The median income for a household in the city is $28,514, and the median income for a family is $32,477. Males have a median income of $26,292 versus $20,529 for females. The per capita income for the city is $17,312. 21.8% of the population and 18.1% of families are below the poverty line. Out of the total people living in poverty, 32.3% are under the age of 18 and 13.6% are 65 or older.
Fort Myers has the Southwest Florida International Airport.