Colby is an unincorporated community in Sandusky County, in the U.S. state of Ohio.
A post office called Colby was established in 1884, and remained in operation until 1905. Besides the post office, Colby had a station on the Nickel Plate Railroad.
Coordinates: 41°15′48″N 82°56′47″W / 41.26333°N 82.94639°W