Time in Indonesia
The Indonesian archipelago geographically stretches across four time zones from in Aceh to in Western New Guinea. However, the Indonesian government recognizes only three time zones in its territory:
- Western Indonesia Time — seven hours ahead of the Coordinated Universal Time
- Central Indonesia Time — eight hours ahead of UTC; and
- Eastern Indonesia Time — nine hours ahead of UTC
Daylight saving time is currently not observed anywhere in Indonesia.
Current usage
In Indonesia, the keeping of standard time is divided into three time zones:| Time zone name | Name in Indonesian | Current time and abbreviation | UTC offset | WIB offset | Area covered | Population | |
| Western Indonesia Time | Waktu Indonesia Barat | WIB+0h | Sumatra, Java, West Kalimantan and Central Kalimantan | 207,485,712 | |||
| Central Indonesia Time | Waktu Indonesia Tengah | WIB+1h | South Kalimantan, East Kalimantan, North Kalimantan, Sulawesi, Bali, West Nusa Tenggara and East Nusa Tenggara | 40,840,394 | |||
| Eastern Indonesia Time | Waktu Indonesia Timur | WIB+2h | Maluku, North Maluku, West Papua and Papua | 6,855,338 |
These time zones were first observed on 1 January 1988. Prior to that date, West and Central Kalimantan used WITA, while Bali belonged to WIB.
Historical usage
During the colonial era, the time zones in Indonesia were regulated as follows:Standardized Time Zone (Indonesia 1932)
- Northern Sumatra Time , was observed in Aceh, Padang and Medan.
- Central and Southern Sumatra Time , was observed in Bengkulu, Palembang and Lampung.
- Java, Bali, and Borneo Time , was observed in Java, Bali, Madura and Kalimantan.
- Celebes Time , was observed in Sulawesi and Lesser Sunda Islands.
- Moluccan Time , was observed in Ternate, Namlea, Ambon and Banda.
- West Irian Time was observed in West Irian. It observed during 1 November 1932 to 31 August 1944.
- Dutch New Guinea Time , was observed in West Irian during named Dutch New Guinea because Netherlands still hold West Irian. It observed from 1 September 1944 to 31 December 1963.
Daylight saving time was observed from 1 November 1932 to 23 March 1942, and from 23 September 1945 to 1 January 1964, except in West Irian, which observed it until 1944. Jakarta, observed daylight saving time only from 1 May 1948 to 1 May 1950.
From 23 March 1942 to 23 September 1945, all regions in Indonesia except West Irian used Japan Standard Time for the sake of the effectiveness of Japanese military operations in Indonesia This meant that western parts of Indonesia observed double daylight saving time and central parts of Indonesia were on daylight saving time during the period of Japanese occupation 1942–1945.
Proposal for a single time zone
IANA time zone database
The IANA time zone database contains four zones for Indonesia in the file zone.tab.- Asia/Jakarta
- Asia/Pontianak
- Asia/Makassar
- Asia/Jayapura