GMT vs IST Time Difference
Comparing Greenwich Mean Time (GMT) and India Standard Time (IST). Live side-by-side clocks, interactive slider, and affected regions.
Switch Comparison Pair:
GMTGreenwich Mean Time
4:23:33 PM
Official civil atomic time
ISTIndia Standard Time
9:53:33 PM
Official civil atomic time
Direct Answer in Plain English
India Standard Time (IST, UTC+5:30) is exactly 5 hours and 30 minutes ahead of Greenwich Mean Time (GMT, UTC+0). When it is 12:00 PM GMT in London, it is 5:30 PM IST in New Delhi.
Offset: 5.5 hour(s) difference
Interactive Time Difference Slider
Slide to instantly convert matching hours between both timezones.
12:00 PM (GMT) = 5:30 PM (IST)
12 AM4 AM8 AM12 PM (Noon)4 PM8 PM11 PM
GMT12:00 PM
IST5:30 PM
Key Cities & States in GMT:
United Kingdom (winter), Iceland, Portugal (winter), Ghana.
Key Cities & States in IST:
Entire Republic of India (New Delhi, Mumbai, Bengaluru, Chennai, Kolkata).
Difference Between IST and GMT in Plain English
India operates on a half-hour offset (UTC+5:30) rather than a whole-hour shift. This single unified timezone covers the entire country of India, spanning 1.4 billion people from Kashmir to Tamil Nadu and Gujarat to Assam.
Daylight Saving Time (DST) Transitions
India does not observe Daylight Saving Time. GMT does not change either, keeping the difference constant at +5 hours 30 minutes in winter (though London switches to BST in summer, reducing the UK-India difference to 4 hours 30 minutes).
Frequently Asked Questions About GMT vs IST
Everything you need to know about comparing GMT and IST.
Google SERP Verified
India Standard Time (IST, UTC+5:30) is exactly 5 hours and 30 minutes ahead of Greenwich Mean Time (GMT, UTC+0). When it is 12:00 PM GMT in London, it is 5:30 PM IST in New Delhi.
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