BST to ACST Converter
BST is not used on this date
This converter uses GMT (GMT +0), the offset London uses on this date. Open the GMT converter.ACST is not used on this date
This converter keeps ACST at GMT +9:30. Adelaide uses ACDT (GMT +10:30) on this date. Open the ACDT converter, or choose Adelaide, Adelaide Hills, or Mount Gambier for city-specific time.Compare BST time with ACST time, including current local time, UTC offsets, time difference, daylight saving changes, working hours, and shareable meeting times.
Time Difference
Greenwich Mean Time is 9 hours and 30 minutes behind Australian Central Standard Time
12:00 pm12:00 in GMT is 9:30 pm21:30 in ACST
GMT to ACST call time
Best time for a conference call or a meeting is between 8am-9am in GMT which corresponds to 5:30pm-6:30pm in ACST
12:00 pm12:00 Greenwich Mean Time (GMT). Offset UTC 0:00 hours
9:30 pm21:30 Australian Central Standard Time (ACST). Offset UTC +9:30 hours
12:00 pm12:00 GMT / 9:30 pm21:30 ACST
| GMT | ACST |
|---|---|
| 12am (midnight) | 9:30 am |
| 1am | 10:30 am |
| 2am | 11:30 am |
| 3am | 12:30 pm |
| 4am | 1:30 pm |
| 5am | 2:30 pm |
| 6am | 3:30 pm |
| 7am | 4:30 pm |
| 8am | 5:30 pm |
| 9am | 6:30 pm |
| 10am | 7:30 pm |
| 11am | 8:30 pm |
| 12pm (noon) | 9:30 pm |
| 1pm | 10:30 pm |
| 2pm | 11:30 pm |
| 3pm | 12:30 am |
| 4pm | 1:30 am |
| 5pm | 2:30 am |
| 6pm | 3:30 am |
| 7pm | 4:30 am |
| 8pm | 5:30 am |
| 9pm | 6:30 am |
| 10pm | 7:30 am |
| 11pm | 8:30 am |
| 00:00 | 09:30 |
| 01:00 | 10:30 |
| 02:00 | 11:30 |
| 03:00 | 12:30 |
| 04:00 | 13:30 |
| 05:00 | 14:30 |
| 06:00 | 15:30 |
| 07:00 | 16:30 |
| 08:00 | 17:30 |
| 09:00 | 18:30 |
| 10:00 | 19:30 |
| 11:00 | 20:30 |
| 12:00 | 21:30 |
| 13:00 | 22:30 |
| 14:00 | 23:30 |
| 15:00 | 00:30 |
| 16:00 | 01:30 |
| 17:00 | 02:30 |
| 18:00 | 03:30 |
| 19:00 | 04:30 |
| 20:00 | 05:30 |
| 21:00 | 06:30 |
| 22:00 | 07:30 |
| 23:00 | 08:30 |
British Summer Time
Offset: BST is 1 hour ahead Greenwich Mean Time (GMT) and is used in Europe
Countries using this time zone: Britain (UK), Guernsey, Isle of Man, Jersey
Principal Cities: The largest city in the BST time zone is London in United Kingdom, with about 7.557 million people. Other major cities in this time zone include Birmingham, Glasgow, Liverpool, Saint Helier.
Greenwich Mean Time (GMT) originally referred to the mean solar time at the Royal Observatory in Greenwich, London. It is now often used to refer to Coordinated Universal Time (UTC) when this is viewed as a time zone, and in casual use for the most parts it is the same. In military GMT is known as Zulu time.Greenwich Mean Time was the same as Universal Time (UT), until the introduction of UTC in 1972 a standard astronomical concept used in many technical fields.
BST representations, usage and related time zones
- +01 - basic short
- +0100 - basic
- +01:00 - extended
- +0100 - sign character (+) followed by a four digit time providing hours (01) and minutes (00) of the offset. Indicates an offset of one hour to the east of the zero meridian.
- Alpha - Military abbreviation for BST
- A - short form of 'Alpha'
- Europe/Belfast
- Europe/Guernsey
- Europe/Isle_of_Man
- Europe/Jersey
- Europe/London
- GB
- GB-Eire
- British Summer Time - UTC +1
- Bangladesh Standard Time - UTC +6
- Bougainville Standard Time - UTC +11
- BST - British Summer Time
- CET - Central European Time
- IST - Irish Standard Time
- WEST - Western European Summer Time
- A - Alpha Time Zone
- CET - Central European Time
- MEZ - Mitteleuropäische Zeit
- WAT - West Africa Time
- WST - Western Sahara Summer Time
- BMT - Biel Mean Time
Australian Central Standard Time
Offset: ACST is 9 hours and 30 minutes ahead Greenwich Mean Time (GMT) and is used in Australia
Countries using this time zone: Australia
Principal Cities: The largest city in the ACST time zone is Darwin in Australia, with about 129,062 people. Other major cities in this time zone include Alice Springs, Palmerston.
Daylight Saving: This is a standard time zone. During summer, some places set clocks forward one hour for daylight saving time and observe Australian Central Daylight Time (ACDT).
End: Australian Central Standard Time (ACST) ended on Sunday, October 5, 2025 at 2:00 am local time and clocks were set one hour forward to Sunday, October 5, 2025, 3:00 am local daylight time instead. Standard time ends annually on the first Sunday of October.
Start: Australian Central Standard Time (ACST) starts on Sunday, April 5, 2026 at 3:00 am local time and clocks are set one hour back to Sunday, April 5, 2026, 2:00 am. Standard time starts annually on the first Sunday of April.
ACST representations, usage and related time zones
- +0930 - basic
- +09:30 - extended
- +0930 - sign character (+) followed by a four digit time providing hours (09) and minutes (30) of the offset. Indicates an offset of nine hours and thirty minutes to the east of the zero meridian.
- Australia/Adelaide
- Australia/Broken_Hill
- Australia/Darwin
- Australia/North
- Australia/South
- Australia/Yancowinna