GMT to IST Time Converter

Convert Greenwich Mean Time to India Standard Time - Quick & Accurate

London (GMT)
Mumbai (IST)
IST is 5 hours 30 minutes ahead of GMT

Quick Time Conversion

London
Greenwich Mean Time
UTC+0 (GMT) / UTC+1 (BST)
Mumbai
India Standard Time
UTC+5:30 (no DST)

Current Time Right Now

Greenwich (GMT/BST)
India (IST)

Updates live every second

24-Hour Visual Comparison

GMT (London)
12am GMT
1am GMT
2am GMT
3am GMT
4am GMT
5am GMT
6am GMT
7am GMT
8am GMT
9am GMT
10am GMT
11am GMT
12pm GMT
1pm GMT
2pm GMT
3pm GMT
4pm GMT
5pm GMT
6pm GMT
7pm GMT
8pm GMT
9pm GMT
10pm GMT
11pm GMT
12a6a12p6p12a
IST (Mumbai)
5am IST
6am IST
7am IST
8am IST
9am IST
10am IST
11am IST
12pm IST
1pm IST
2pm IST
3pm IST
4pm IST
5pm IST
6pm IST
7pm IST
8pm IST
9pm IST
10pm IST
11pm IST
12am IST
1am IST
2am IST
3am IST
4am IST
5:30a11:30a5:30p11:30p5:30a
Business Hours (9AM-5PM)
Evening (5PM-9PM)
Night (9PM-6AM)

Hover over any hour to see corresponding time in both zones

Best Time for Meeting/Call

To schedule a meeting between GMT and IST:

Best Window (GMT)
9:00 AM - 2:30 PM
Which is (IST)
2:30 PM - 8:00 PM
Both parties in working hours
5.5-hour overlap window
Ideal for UK-India collaboration

Pro Tip: Schedule calls between 10:00 AM - 1:00 PM GMT for optimal overlap with Indian business hours (3:30 PM - 6:30 PM IST)

Complete GMT to IST Conversion Table

GMT TimeIST TimeContext
12:00 AM05:30 AM
Midnight GMT
01:00 AM06:30 AM
Early Morning GMT
02:00 AM07:30 AM
Early Morning GMT
03:00 AM08:30 AM
Early Morning GMT
04:00 AM09:30 AM
Early Morning GMT
05:00 AM10:30 AM
Early Morning GMT
06:00 AM11:30 AM
Morning Starts GMT
07:00 AM12:30 PM
Night Time
08:00 AM01:30 PM
Night Time
09:00 AM02:30 PM
Work Starts GMT
10:00 AM03:30 PM
GMT Business Hours
11:00 AM04:30 PM
GMT Business Hours

Greenwich Mean Time (GMT)

UTC+0
UTC+1 during BST
Major Cities:
  • • London
  • • Manchester
  • • Birmingham
  • • Liverpool
  • • Edinburgh
Daylight Saving:

BST (UTC+1) from March to October

IANA Identifier:

Europe/London

India Standard Time (IST)

UTC+5:30
No DST observed
Major Cities:
  • • Mumbai
  • • Delhi
  • • Bangalore
  • • Kolkata
  • • Chennai
Daylight Saving:

Not observed - constant UTC+5:30 year-round

IANA Identifier:

Asia/Kolkata

Greenwich Mean Time (GMT) vs India Standard Time (IST)

Greenwich Mean Time (GMT)India Standard Time (IST)

Greenwich Mean Time (GMT) is the time zone at longitude 0°, the prime meridian. It is equivalent to Coordinated Universal Time (UTC+0). During summer, the UK observes British Summer Time (BST), which is UTC+1.

India Standard Time (IST) is 5 hours and 30 minutes ahead of UTC (UTC+5:30). India does not observe Daylight Saving Time and maintains the same offset year-round across the entire country.

Where Is It Used?

  • United Kingdom: England, Scotland, Wales, Northern Ireland
  • Crown Dependencies: Isle of Man, Jersey, Guernsey
  • British Overseas Territories: Some territories including Gibraltar
  • Major Cities: London, Manchester, Birmingham, Liverpool, Glasgow, Edinburgh, Cardiff, Belfast
  • Historical: Formerly used as the global time standard before UTC
  • India: Entire country uses a single time zone
  • Major Cities: Mumbai, Delhi, Bangalore, Kolkata, Chennai, Hyderabad, Ahmedabad, Pune
  • Population: Used by over 1.4 billion people
  • Also Used In: Sri Lanka (often uses same offset)
  • Uniqueness: One of few time zones with 30-minute offset from UTC

Geographic & Economic Information

Geographic Features

  • Location: Island nation in Northwestern Europe
  • Prime Meridian: Runs through Greenwich, London
  • Climate: Temperate maritime

Economic Significance

  • Financial Hub: London is a global financial center
  • Currency: British Pound Sterling (GBP)
  • Industries: Finance, technology, pharmaceuticals, aerospace

Geographic Features

  • Location: South Asia, Indian subcontinent
  • Size: 7th largest country by area
  • Climate: Tropical to temperate, monsoon season

Economic Significance

  • Tech Hub: Major IT and software outsourcing center
  • Currency: Indian Rupee (INR)
  • Industries: IT services, pharmaceuticals, textiles, agriculture
  • Growing Economy: One of the fastest-growing major economies

Key Facts

  • UTC Offset: UTC+0 (GMT) / UTC+1 (BST)
  • Historical: Reference point for world timekeeping
  • Population: Approximately 67 million
  • Language: English (official)
  • Daylight Saving: BST from last Sunday in March to last Sunday in October
  • Business Hours: Typically 9:00 AM - 5:00 PM
  • UTC Offset: UTC+5:30 (constant year-round)
  • Time Zone Count: Single time zone for entire country
  • Population: Over 1.4 billion (2nd most populous)
  • Languages: Hindi and English (official), 22 scheduled languages
  • Daylight Saving: Not observed
  • Business Hours: Typically 9:00 AM - 6:00 PM or 10:00 AM - 7:00 PM

Quick Reference

Time Difference: IST is 5 hours 30 minutes ahead of GMT (4 hours 30 minutes during BST)
Seasonal Variation: Time difference changes when UK switches between GMT and BST
Distance: Approximately 4,500 miles between London and Mumbai
UTC Offsets: GMT = UTC+0, IST = UTC+5:30 | BST = UTC+1 (summer)
2025 BST: Starts March 30 at 1:00 AM, Ends October 26 at 2:00 AM

Frequently Asked Questions

IST (India Standard Time) is 5 hours and 30 minutes ahead of GMT (Greenwich Mean Time). When it's 12:00 PM in London (GMT), it's 5:30 PM in Mumbai (IST).

The best time to call from GMT to IST is between 9:00 AM and 2:30 PM GMT, which corresponds to 2:30 PM to 8:00 PM IST. This ensures both parties are within reasonable working or waking hours.

Yes, the time difference varies. During GMT (winter), IST is 5 hours 30 minutes ahead. During BST (British Summer Time, UTC+1), IST is only 4 hours 30 minutes ahead. India does not observe Daylight Saving Time.

GMT cities include London, Manchester, Birmingham, Liverpool, and Edinburgh. IST cities include Mumbai, Delhi, Bangalore, Kolkata, and Chennai.

India uses UTC+5:30 to maintain a single time zone across the entire country despite its geographical width. The 30-minute offset helps center the timezone on India's longitude, avoiding the need for multiple time zones.

Related Time Converters

IST → GMTGMT → UTCIST → PSTGMT → ESTIST → ESTGMT → PSTIST → JSTView All