SuperCalc

Mumbai to London Time Converter

Convert time between Mumbai and London. Right now, Mumbai is 4h 30m ahead of London.

IST · Mumbai
1:04 AM
UTC +5:30 · India
GMT · London
8:34 PM
UTC +1 · UK
Time across cities

Time Zone Converter

Click any hour to see what it lands on in every city. The first row's hours run 12am to 11pm — every other row is its local time at the same instant.

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Mumbai
UTC +5:30anchor
London
UTC +1
Right now
Mumbai
1:04 AM
Sun, May 10
London
8:34 PM
Sat, May 9
Quick reference

When it's this time in Mumbai:

MumbaiLondon
6:00 AM1:30 AM
9:00 AM4:30 AM
12:00 PM7:30 AM
3:00 PM10:30 AM
6:00 PM1:30 PM
9:00 PM4:30 PM

About IST and GMT

IST (India Standard Time) covers India and is anchored to the IANA zone Asia/Kolkata. It does not observe daylight saving time — the offset stays fixed all year.

GMT (Greenwich Mean Time) covers UK, Ireland, Iceland, and Portugal via Europe/London. It observes daylight saving time, so the gap between these two zones shifts twice a year.

Because at least one of these zones uses DST, the time difference between IST and GMT is not constant — it shifts by an hour during the spring and autumn DST transitions. The hour grid below recomputes the difference for any specific date you click, using the IANA rules baked into your browser.

FAQ

How many hours difference between IST and GMT?
Right now, IST is 4h 30m ahead of GMT. Because at least one of these zones observes daylight saving time, the gap shifts by an hour twice a year (spring and autumn). The hour grid above recomputes correctly for any specific date.
What time is 9 AM IST in GMT?
9 AM IST (Mumbai) is 4:30 AM GMT (London) today. Click any cell in the grid above to convert other times — the math handles DST and half-hour offsets correctly.
Does IST observe daylight saving time?
No. India Standard Time stays at a fixed offset year-round. The hour grid above will show the same difference whether you check in summer or winter.
What's the IANA timezone identifier for IST and GMT?
IST → Asia/Kolkata. GMT → Europe/London. We use IANA identifiers (not GMT offsets) as the source of truth so historical and future dates remain accurate, including across DST changes and political timezone shifts.
Where can I see the overlap between IST and GMT working hours?
Click "Working hrs" in the toolbar above to highlight hours where all selected cities have overlapping business hours. The amber highlight shows which columns work for scheduling meetings across time zones.
Which countries use IST and GMT?
IST (India Standard Time) is used in India. GMT (Greenwich Mean Time) is used in UK, Ireland, Iceland, and Portugal. If you're converting time between any of these countries, this is the right page.