ChST to BST Converter
The United Kingdom is on standard time: GMT (UTC+0) until Sun, Mar 28, 2027.
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Selected conversion
10:00 pm22:00 ChST (UTC+10), Nov 1, 2026 = 12:00 pm12:00 GMT (UTC+0), Nov 1, 2026
ChST is 10 hours ahead of GMT.
ChST and BST examples
These examples always use ChST (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.
ChST is 9 hours ahead of BST.
How the time difference changes
For most of the year, ChST is 9 hours ahead of BST. From Oct 25, 2026 to Mar 28, 2027, and from Oct 31, 2027 to Mar 26, 2028, ChST is 10 hours ahead of GMT.
For most of the year, working hours of 9:00 am to 6:00 pm in ChST correspond to 12:00 am to 9:00 am in BST. At other times of the year, working hours of 9:00 am to 6:00 pm in ChST correspond to 11:00 pm (previous day) to 8:00 am in GMT.For most of the year, working hours of 09:00 to 18:00 in ChST correspond to 00:00 to 09:00 in BST. At other times of the year, working hours of 09:00 to 18:00 in ChST correspond to 23:00 (previous day) to 08:00 in GMT.
Compare ChST time with BST time, including current local time, UTC offsets, time difference, daylight saving changes, working hours, and shareable meeting times.
Time Difference
Chamorro Standard Time is 10 hours ahead of Greenwich Mean Time.
10:00 pm22:00 in ChST is 12:00 pm12:00 in GMT
ChST to GMT call time
Best time for a conference call or a meeting is between 6pm-7pm18:00-19:00 in ChST which corresponds to 8am-9am08:00-09:00 in GMT. Their 9am–6pm09:00–18:00 working hours do not overlap; this is a suggested compromise.
10:00 pm22:00 Chamorro Standard Time (ChST). Offset UTC +10:00 hours
12:00 pm12:00 Greenwich Mean Time (GMT). Offset UTC 0:00 hours
10:00 pm22:00 ChST / 12:00 pm12:00 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.
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Chamorro Standard Time
Offset: ChST is 10 hours ahead of Greenwich Mean Time (GMT).
Countries using this time zone: Guam, Northern Mariana Islands
Principal Cities: The largest city in the ChST time zone is Saipan in the Northern Mariana Islands, with about 48,220 people. Other major cities in this time zone include Dededo Village, Yigo Village, Tamuning-Tumon-Harmon Village, Mangilao Village.
Daylight Saving: Clocks in Chamorro Standard Time (ChST) do not change for daylight saving time, so ChST stays the same throughout the year. Other time zones may set clocks forward in summer and back in winter; see upcoming clock changes worldwide.
ChST 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 east of the zero meridian.
- Kilo - Military abbreviation for ChST
- K - short form of 'Kilo'
- Pacific/Guam
- Pacific/Saipan
- AEST - Australian Eastern Standard Time
- CHUT - Chuuk Time
- ChST - Chamorro Standard Time
- K - Kilo Time Zone
- KDT - Korea Daylight Time
- PGT - Papua New Guinea Time
- VLAT - Vladivostok Time
- YAKST - Yakutsk Summer Time
- YAPT - Yap Time
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