BST to HDT 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.HDT is not used on this date
This converter keeps HDT at GMT -9. Honolulu uses HST (GMT -10) on this date. Open the HST converter, or choose Honolulu, Pearl City, or Hilo for city-specific time.Quick answers
Selected conversion
The selected date and time will appear here when the converter loads.
BST and HDT examples
These examples always use BST (UTC+1) and HDT (UTC-9). They stay the same when you change the date or time above. The selected conversion may differ when daylight saving time applies.
BST is 10 hours ahead of HDT.
How the time difference changes
For most of the year, BST is 10 hours ahead of HDT. At other times of the year, GMT is 9 hours ahead of HDT.
For most of the year, working hours of 9:00 am to 5:00 pm in BST correspond to 11:00 pm (previous day) to 7:00 am in HDT. At other times of the year, working hours of 9:00 am to 5:00 pm in GMT correspond to 12:00 am to 8:00 am in HDT.
Compare BST time with HDT 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 ahead of Hawaii Daylight Time
12:00 pm12:00 in GMT is 3:00 am03:00 in HDT
GMT to HDT call time
Best time for a conference call or a meeting is between 5pm-6pm in GMT which corresponds to 8am-9am in HDT
12:00 pm12:00 Greenwich Mean Time (GMT). Offset UTC 0:00 hours
3:00 am03:00 Hawaii Daylight Time (HDT). Offset UTC -9:00 hours
12:00 pm12:00 GMT / 3:00 am03:00 HDT
| GMT | HDT |
|---|---|
| 12am (midnight) | 3pm |
| 1am | 4pm |
| 2am | 5pm |
| 3am | 6pm |
| 4am | 7pm |
| 5am | 8pm |
| 6am | 9pm |
| 7am | 10pm |
| 8am | 11pm |
| 9am | 12am (midnight) |
| 10am | 1am |
| 11am | 2am |
| 12pm (noon) | 3am |
| 1pm | 4am |
| 2pm | 5am |
| 3pm | 6am |
| 4pm | 7am |
| 5pm | 8am |
| 6pm | 9am |
| 7pm | 10am |
| 8pm | 11am |
| 9pm | 12pm (noon) |
| 10pm | 1pm |
| 11pm | 2pm |
| 00:00 | 15:00 |
| 01:00 | 16:00 |
| 02:00 | 17:00 |
| 03:00 | 18:00 |
| 04:00 | 19:00 |
| 05:00 | 20:00 |
| 06:00 | 21:00 |
| 07:00 | 22:00 |
| 08:00 | 23:00 |
| 09:00 | 00:00 |
| 10:00 | 01:00 |
| 11:00 | 02:00 |
| 12:00 | 03:00 |
| 13:00 | 04:00 |
| 14:00 | 05:00 |
| 15:00 | 06:00 |
| 16:00 | 07:00 |
| 17:00 | 08:00 |
| 18:00 | 09:00 |
| 19:00 | 10:00 |
| 20:00 | 11:00 |
| 21:00 | 12:00 |
| 22:00 | 13:00 |
| 23:00 | 14:00 |
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 8.962 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
Hawaii Daylight Time
Offset: HDT is 9 hours behind Greenwich Mean Time (GMT) and is used in Pacific
Countries using this time zone: United States
HDT representations, usage and related time zones
- -09 - basic short
- -0900 - basic
- -09:00 - extended
- -0900 - sign character (-) followed by a four digit time providing hours (09) and minutes (00) of the offset. Indicates an offset of nine hours to the west of the zero meridian.
- Victor - Military abbreviation for HDT
- V - short form of 'Victor'
- America/Adak
- America/Atka
- US/Aleutian
- AKST - Alaska Standard Time
- AHDT - Alaska-Hawaii Daylight Time
- HADT - Hawaii-Aleutian Daylight Time
- GAMT - Gambier Time
- HDT - Hawaii Daylight Time
- V - Victor Time Zone