GMT to IST Converter (Greenwich Mean Time to India Time)

IST is 5 hours 30 minutes ahead of GMT.

Greenwich Mean Time is the time at the Royal Observatory in Greenwich and the UK's winter clock. India Standard Time is UTC+05:30, a fixed 5 hours 30 minutes ahead of GMT. Neither of the two time scales has any daylight saving shift, so the difference is the same on every day of the year.

The wrinkle is that London itself does not stay on GMT. In summer, the UK uses British Summer Time (UTC+01:00), and a person in London is only 4 hours 30 minutes behind India. This converter takes GMT as a fixed time scale, and the page for UTC gives the same figures.

How to use this tool

1. Pick a date and time in GMT. The date matters when daylight saving time is in force.
2. Read the matching time in IST, with both UTC offsets.
3. Use "Use current time" for now, or the tables below for a quick look.

Formula

IST time = GMT time − (GMT UTC offset) + (IST UTC offset)

The converter looks up both UTC offsets for the actual instant in the saved IANA time zone rules, so daylight saving changes are included automatically.

Example

Worked with the saved rules:

9:00 AM GMT on March 2, 2026 = 2:30 PM IST

6:30 PM GMT on August 3, 2026 = 12:00 AM IST (next day)

Time difference through the year

The difference depends on the date when either place moves its clocks. These are the offsets on two reference days, from the saved IANA rules:

Clock changes in 2026

Greenwich Mean Time and India Standard Time do not change clocks in this year, so the difference stays the same all year.

GMT to IST time table

Each hour in Greenwich Mean Time with the matching India Standard Time time.

IST to GMT time table

Each hour in India Standard Time with the matching Greenwich Mean Time time.

Hours that work in both places

Hours (on the January reference day) that fall between 8:00 AM and 8:00 PM in both GMT and IST:

GMT versus London time

In 2026 the UK moves its clocks forward on March 29 and back on October 25. Between those dates a message that says "GMT" while meaning "London time" is off by an hour. When you plan with an office in London, ask whether the time is the local clock or GMT.

India keeps the same time all year, so the only variation in a London-India call comes from the British side.

Cricket, broadcasts and trade

Test matches in England usually begin at 11:00 a.m. local time, which is 3:30 p.m. in India when London is on British Summer Time. Broadcasters in India rely on a fixed conversion from the local UK time to the Indian schedule.

UK-India trade, university applications and visa appointments also involve a fixed 5:30 offset in winter. A deadline of 5:00 p.m. GMT is 10:30 p.m. in India.