HST to BST Converter
Start by searching for a time zone, city, or town.
Add one or more places to compare local times, adjust the date, and share the result.
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Selected conversion
7:30 am07:30 HST (UTC-10), Nov 1, 2026 = 5:30 pm17:30 GMT (UTC+0), Nov 1, 2026
HST is 10 hours behind GMT.
HST and BST examples
These examples always use HST (UTC-10) and BST (UTC+1). They stay the same when you change the date or time above. The selected conversion may differ when daylight saving time applies.
HST is 11 hours behind BST.
How the time difference changes
For most of the year, HST is 11 hours behind BST. From Oct 25, 2026 to Mar 28, 2027, and from Oct 31, 2027 to Mar 26, 2028, HST is 10 hours behind GMT.
For most of the year, working hours of 9:00 am to 6:00 pm in HST correspond to 8:00 pm to 5:00 am (next day) in BST. At other times of the year, working hours of 9:00 am to 6:00 pm in HST correspond to 7:00 pm to 4:00 am (next day) in GMT.For most of the year, working hours of 09:00 to 18:00 in HST correspond to 20:00 to 05:00 (next day) in BST. At other times of the year, working hours of 09:00 to 18:00 in HST correspond to 19:00 to 04:00 (next day) in GMT.
Compare HST time with BST time, including current local time, UTC offsets, time difference, daylight saving changes, working hours, and shareable meeting times.
Time Difference
Hawaii Standard Time is 10 hours behind Greenwich Mean Time.
7:30 am07:30 in HST is 5:30 pm17:30 in GMT
HST to GMT call time
Best time for a conference call or a meeting is between 8am-9am08:00-09:00 in HST which corresponds to 6pm-7pm18:00-19:00 in GMT. Their 9am–6pm09:00–18:00 working hours do not overlap; this is a suggested compromise.
7:30 am07:30 Hawaii Standard Time (HST). Offset UTC -10:00 hours
5:30 pm17:30 Greenwich Mean Time (GMT). Offset UTC 0:00 hours
7:30 am07:30 HST / 5:30 pm17:30 GMT
Choose an hour to update the converter. Day labels such as “next day” or “+1” are relative to the selected date in the first column. Use Up and Down arrow keys, Home or End to move between hours, then Enter or Space to select.
| HST | GMT |
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Hawaii Standard Time
Offset: HST is 10 hours behind Greenwich Mean Time (GMT).
Countries using this time zone: United States
Principal Cities: The largest city in the HST time zone is Honolulu in the United States, with about 350,964 people. Other major cities in this time zone include Pearl City, Hilo, Kailua, Waipahu.
Daylight Saving: Some places on Hawaii Standard Time (HST) keep the same time all year, while others use HST for only part of the year and change their clocks for daylight saving time; see upcoming clock changes worldwide.
Today all shaded areas are on HST.
HST representations, usage and related time zones
- -10 - basic short
- -1000 - basic
- -10:00 - extended
- -1000 - sign character (-) followed by a four digit time providing hours (10) and minutes (00) of the offset. Indicates an offset of ten hours to the west of the zero meridian.
- Whiskey - Military abbreviation for HST
- W - short form of 'Whiskey'
- America/Adak
- America/Atka
- HST
- Pacific/Honolulu
- Pacific/Johnston
- US/Aleutian
- US/Hawaii
- HAST - Hawaii-Aleutian Standard Time
- CKT - Cook Island Time
- HST - Hawaii Standard Time
- TAHT - Tahiti Time
- W - Whiskey Time Zone
British Summer Time
Offset: BST is 1 hour ahead of Greenwich Mean Time (GMT).
Countries using this time zone: Guernsey, Isle of Man, Jersey, United Kingdom
Principal Cities: The largest city in the BST time zone is London in the United Kingdom, with about 8.962 million people. Other major cities in this time zone include Birmingham, Glasgow, Manchester, Sheffield.
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 the two are the same. In the military, GMT is known as Zulu time. Greenwich Mean Time was the same as Universal Time (UT), a standard astronomical concept used in many technical fields, until the introduction of UTC in 1972.
Current time in the United Kingdom: UK time now
Today the shaded areas are on UTC+0 (GMT).
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