According to the 2021 census gazetteer files, Sheldon Township has a total area of 39.67 square miles (102.74 km2), all land.

[2] (This list is based on USGS data and may include former settlements.)

As of the 2020 census[1] there were 1,239 people, 668 households, and 393 families residing in the township.

There were 580 housing units at an average density of 14.62 per square mile (5.64/km2).

37.00% of all households were made up of individuals, and 12.30% had someone living alone who was 65 years of age or older.