GMT to IST time converter

Enter a time in GMT to get the matching time in IST, whether it falls on the next or previous day, and a full 24-hour table. Handy for planning calls between London in winter and Mumbai and New Delhi.

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How to use it

  1. Enter time in gmt and day in gmt (optional).
  2. The result appears straight away and updates as you edit.
  3. Copy the result, or copy a link that keeps the same values to share it.

How it is calculated

IST time = GMT time + 5.5 hours, because IST is UTC+5:30 and GMT is UTC+0. If the result reaches 24:00 or more, subtract 24 hours and move to the next day; if it drops below 00:00, add 24 hours and move to the previous day.

Example

Inputs: Time in GMT = 22:00, Day in GMT (optional) = Thursday. Result: Time in IST: 03:30; Day change: Next day (+1); Offset difference (IST minus GMT): 5.5 hours.

Limits and caveats

  • Fixed offsets are used: GMT = UTC+0 and IST = UTC+5:30, whatever the date.
  • London leaves GMT for BST (UTC+1) from the last Sunday of March to the last Sunday of October; the tool does not apply that change.
  • IST here is India Standard Time (UTC+5:30), not Irish or Israel time.

Questions about this tool

What time is 09:00 GMT in IST?

09:00 GMT is 14:30 IST on the same day, because IST is 5.5 hours ahead of GMT.

Does daylight saving time change the result?

The tool keeps GMT at UTC+0 all year. London leaves GMT for BST (UTC+1) from the last Sunday of March to the last Sunday of October; in that period the gap between London and IST is 4.5 hours.

Which IST does this tool use?

Here IST means India Standard Time, UTC+5:30. The same letters are used for Irish Standard Time (UTC+1, Irish summer time) and Israel Standard Time (UTC+2).