Western Indonesian Time

The Indonesian archipelago geographically stretches across four time zones from UTC+6 in Aceh to UTC+9 in Western Papua. However, The Indonesian government only recognizes three time zones in its territory:

The boundary between the western and central time zones established is a line running north between Java and Bali through the center of Kalimantan. The border between central and eastern time zones runs north from the eastern tip of Timor to the eastern tip of Sulawesi.

Daylight saving time is not currently observed in almost all of Indonesia due to its tropical location, resulting in those areas using their respective time zone all year long. The only unofficial exception of this is Muara Teweh and Maurainu, which unofficially uses Western Indonesian Daylight Time.

In Indonesia, the keeping of standard time is divided into three time zones:

Indonesia Western Standard Time (IWST) (WIB, Indonesian: Waktu Indonesia Barat) (UTC+07:00) is observed in:

IANA time zone database identifiers are "Asia/Jakarta" and "Asia/Pontianak"

Indonesia Central Standard Time (ICST) (WITA, Indonesian: Waktu Indonesia Tengah) (UTC+08:00) is observed in:

IANA time zone database identifier is "Asia/Makassar"

Indonesia Eastern Standard Time (IEST) (WIT, Indonesian: Waktu Indonesia Timur) (UTC+09:00) is observed in:

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