Tangail (Ṭāṅgāila Jēlā) is a district (zila) in the central region of Bangladesh. It was a small mohakuma in the nation until it occupied one-third land of Mymensingh district during Pakistan dictatorship. In 1969, Tangail district was created by Tangail Mohokuma from its 237 square kilometers of land and 3177 square kilometers of land acquired from Mymensingh district. It is the largest district of Dhaka division by area and second largest by population (after Dhaka district). The population of Tangail zila is about 4 million and its area is . The main city of the district is Tangail. It is surrounded by Jamalpur District on the north, the Dhaka and Manikganj Districts on the south, the Mymensingh and Gazipur on the east, and the Sirajganj on the west.
Until 1969, Tangail was a part of Greater Mymensingh. In 1969 the Tangail District was established. Tangail district was created by Tangail Mohokuma from its 237 square kilometers of land and 3177 square kilometers of land acquired from Mymensingh district. The main rivers that cross the Tangail district are the Jamuna, Dhaleshwari, Jhenai, Bangshi, Louhajang, Langulia, Elongjani, Jugni, Pouli, Fotikjani and the Turag.
The subdivision of Tangail was established in 1870. It was turned into a district on 1 December 1969. The district consists of 11 municipalities, 108 wards of these municipalities, 109 Union Parishads and 2516 villages.
Tangail district is subdivided into 12 Upazilas:
Tangail Sadar Upazila
Sakhipur Upazila
Basail Upazila
Madhupur Upazila
Ghatail Upazila
Kalihati Upazila
Nagarpur Upazila
Mirzapur Upazila
Gopalpur Upazila
Delduar Upazila
Bhuapur Upazila
Dhanbari Upazila
According to the 2022 Census of Bangladesh, Tangail District had 1,061,749 households and a population of 4,037,608, 29.2% of whom lived in urban areas. The population density was 1,183 people per km2. The literacy rate (age 7 and over) was 69.6%, compared to the national average of 74.7%.
Muslims make up 92.72% and 6.83% are Hindus. There is a small population of Christians near Madhupur National Park, mainly Garo tribals.