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

GMT is 5 hours 30 minutes behind IST.

India Standard Time runs 5 hours 30 minutes ahead of GMT, so converting from IST means subtracting 5 hours 30 minutes. A 3:30 p.m. close in India is 10:00 a.m. GMT. The same offset applies every day, since India and GMT are both free of seasonal clock changes.

People searching for this direction are often reading a timestamp, a broadcast schedule or a message from India and need the matching moment in London, in a server log or in a document that lists GMT. The reverse page covers the same pair read from the UK side.

How to use this tool

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

Formula

GMT time = IST time − (IST UTC offset) + (GMT 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 IST on March 2, 2026 = 3:30 AM GMT

6:30 PM IST on August 3, 2026 = 1:00 PM GMT

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

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

IST to GMT time table

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

GMT to IST time table

Each hour in Greenwich Mean Time with the matching India Standard 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 IST and GMT:

Timestamps and international schedules

GMT appears in email headers, airline schedules, shipping notices and software logs. A product launch listed as 9:00 a.m. IST happens at 3:30 a.m. GMT, which may mean the previous night for a viewer on the US East Coast.

Where a document says GMT, it most often means the same moment as UTC. If it says "UK time", it can mean GMT in winter and BST in summer, and the difference with India then changes with the season.

Business calls with the UK

Indian offices typically open at 9:30 a.m., which is 4:00 a.m. GMT. London opens at around 9:00 a.m., or 2:30 p.m. in India in winter. The overlap is therefore the Indian afternoon and the UK morning, and it shrinks by an hour of local time in summer.

To set a recurring meeting, fix it to a local time at one site and check the other site on the weeks in March and October when the UK changes its clocks.