As of 2015, Indonesian Railways operates:
409 locomotive units;
572 electric multiple units;
108 diesel multiple units;
1,507 passenger coaches; and
6,499 freight cars
Railway lines: 5,042 kilometres (3,133 mi)
The first railways in Indonesia were built on the island of Java, using 1,435 mm (4 ft 8 1⁄2 in) gauge.
During the Japanese occupation, they were converted to 1,067 mm (3 ft 6 in) gauge, although 1,435 mm (4 ft 8 1⁄2 in) and 750 mm (2 ft 5 1⁄2 in) lines previously existed.
Newer constructions in Aceh and Sulawesi are using the 1,435 mm gauge. Most of the Jakarta metropolitan area is electrified at 1500 V DC overhead.
The majority of Indonesia's railways is located on Java, used for both passenger and freight transport.
There are three separate railway networks on Sumatra: one in Aceh and North Sumatra, another in West Sumatra, and the final one in South Sumatra and Lampung with two new networks is being developed in Kalimantan and Sulawesi.
Indonesia's railways are operated by the state-owned PT Kereta Api Indonesia (KAI) and its Jakartan subsidiary, the PT Kereta Commuter Indonesia (KCI).
Airport train services in several cities is run by PT Railink, an Indonesian railway subsidiaries with a joint venture with state-owned airport service company.
Indonesian Railways is a major customer of the state owned railway industry, PT Industri Kereta Api (INKA), by using passenger coaches, freight wagons and electric multiple units manufactured and assembled by the Madiun based company in East Java. INKA was founded in 1981. Its trains have operated in the Philippines, Malaysia, Thailand, Singapore, Australia and from 2006 it has been involved in Bangladesh.