Tolono is a village in Tolono Township, Champaign County, Illinois, United States. The population was 3,447 at the 2010 census. Its name was fabricated by J.B. Calhoun, land commission of the Illinois Central Railroad, who wrote about it simply: "[I] placed the vowel o three times, thus o-o-o, and filling in with the consonants t-l-n."
Tolono is located at 39°59′10″N 88°15′35″W (39.986046, -88.259727). According to the history of Champaign County: A surveyor for the Illinois Central who was looking for a division headquarters, surveyed the Tolono area and wrote on a map 'too low, No.' and that became the name of the town established there. Tolono as one time had two or three companies making tile used to drain the land around the town, resulting in swamps on the east side of the town both on the north and south side of the Wabash Railroad.
According to the 2010 census, Tolono has a total area of 2.14 square miles (5.54 km2), all land.
As of the census of 2000, there were 2,700 people, 1,083 households, and 753 families residing in the village. The population density was 1,444.4 people per square mile (557.5/km²). There were 1,137 housing units at an average density of 608.3 per square mile (234.8/km²). The racial makeup of the village was 97.78% White, 0.30% African American, 0.52% Native American, 0.15% Asian, 0.11% Pacific Islander, 0.37% from other races, and 0.78% from two or more races. Hispanic or Latino of any race were 0.93% of the population.