BST to IST Converter
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Quick answers
Selected conversion
12:00 pm12:00 GMT (UTC+0), Oct 28, 2026 = 5:30 pm17:30 IST (UTC+5:30), Oct 28, 2026
GMT is 5 hours and 30 minutes behind IST.
BST and IST examples
These examples always use BST (UTC+1) and IST (UTC+5:30). They stay the same when you change the date or time above. The selected conversion may differ when daylight saving time applies.
BST is 4 hours and 30 minutes behind IST.
How the time difference changes
For most of the year, BST is 4 hours and 30 minutes behind IST. From Oct 25, 2026 to Mar 28, 2027, GMT is 5 hours and 30 minutes behind IST.
For most of the year, working hours of 9:00 am to 6:00 pm in BST correspond to 1:30 pm to 10:30 pm in IST. At other times of the year, working hours of 9:00 am to 6:00 pm in GMT correspond to 2:30 pm to 11:30 pm in IST.For most of the year, working hours of 09:00 to 18:00 in BST correspond to 13:30 to 22:30 in IST. At other times of the year, working hours of 09:00 to 18:00 in GMT correspond to 14:30 to 23:30 in IST.
Compare BST time with IST time, including current local time, UTC offsets, time difference, daylight saving changes, working hours, and shareable meeting times.
Time Difference
Greenwich Mean Time is 5 hours and 30 minutes behind India Standard Time.
12:00 pm12:00 in GMT is 5:30 pm17:30 in IST
GMT to IST call time
Best time for a conference call or a meeting is between 9am-12:30pm09:00-12:30 in GMT which corresponds to 2:30pm-6pm14:30-18:00 in IST
12:00 pm12:00 Greenwich Mean Time (GMT). Offset UTC 0:00 hours
5:30 pm17:30 India Standard Time (IST). Offset UTC +5:30 hours
12:00 pm12:00 GMT / 5:30 pm17:30 IST
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.
| GMT | IST |
|---|---|
| 5:30am | |
| 6:30am | |
| 7:30am | |
| 8:30am | |
| 9:30am | |
| 10:30am | |
| 11:30am | |
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| 1:30pm | |
| 2:30pm | |
| 3:30pm | |
| 4:30pm | |
| 5:30pm | |
| 6:30pm | |
| 7:30pm | |
| 8:30pm | |
| 9:30pm | |
| 10:30pm | |
| 11:30pm | |
| 12:30am next day | |
| 1:30am next day | |
| 2:30am next day | |
| 3:30am next day | |
| 4:30am next day | |
| 05:30 | |
| 06:30 | |
| 07:30 | |
| 08:30 | |
| 09:30 | |
| 10:30 | |
| 11:30 | |
| 12:30 | |
| 13:30 | |
| 14:30 | |
| 15:30 | |
| 16:30 | |
| 17:30 | |
| 18:30 | |
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| 23:30 | |
| 00:30 next day | |
| 01:30 next day | |
| 02:30 next day | |
| 03:30 next day | |
| 04:30 next day |
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
India Standard Time
Offset: IST is 5 hours and 30 minutes ahead of Greenwich Mean Time (GMT).
Countries using this time zone: India
Principal Cities: The largest city in the IST time zone is Mumbai in India, with about 12.692 million people. Other major cities in this time zone include Delhi, Bengaluru, Hyderabad, Ahmedabad.
Daylight Saving: Clocks in India Standard Time (IST) do not change for daylight saving time, so IST stays the same throughout the year. Other time zones may set clocks forward in summer and back in winter; see upcoming clock changes worldwide.
Current time in India: India time now
IST representations, usage and related time zones
- +0530 - basic
- +05:30 - extended
- +0530 - sign character (+) followed by a four digit time providing hours (05) and minutes (30) of the offset. Indicates an offset of five hours and thirty minutes to the east of the zero meridian.
- Asia/Calcutta
- Asia/Kolkata
- India Standard Time - UTC +5:30
- Irish Standard Time - UTC +1
- Israel Standard Time - UTC +2