GMT to AEST Time Converter

Convert Greenwich Mean Time to Australian Eastern Standard Time - Quick & Accurate

London (GMT)
Sydney (AEST)
AEST is 10 hours ahead of GMT (varies 9-11 with DST)

Quick Time Conversion

London
Greenwich Mean Time
UTC+0 (GMT) / UTC+1 (BST)
Sydney
Australian Eastern Standard Time
UTC+10 (AEST) / UTC+11 (AEDT)

Current Time Right Now

Greenwich (GMT/BST)
Australian Eastern (AEST/AEDT)

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
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AEST (Sydney)
10am AEST
11am AEST
12pm AEST
1pm AEST
2pm AEST
3pm AEST
4pm AEST
5pm AEST
6pm AEST
7pm AEST
8pm AEST
9pm AEST
10pm AEST
11pm AEST
12am AEST
1am AEST
2am AEST
3am AEST
4am AEST
5am AEST
6am AEST
7am AEST
8am AEST
9am AEST
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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 AEST:

Best Window (GMT)
8:00 AM - 10:00 AM
Which is (AEST)
6:00 PM - 8:00 PM
Very limited overlap due to 10-hour difference
GMT morning = AEST evening
2-hour window for UK-Australia collaboration

Pro Tip: Schedule calls at 9:00 AM GMT for optimal timing - early enough for UK business hours while still reasonable evening time (7:00 PM) in Sydney

Complete GMT to AEST Conversion Table

GMT TimeAEST TimeContext
12:00 AM11:00 AM
Midnight GMT
01:00 AM12:00 PM
Late Night UK
02:00 AM01:00 PM
Late Night UK
03:00 AM02:00 PM
Late Night UK
04:00 AM03:00 PM
Late Night UK
05:00 AM04:00 PM
Late Night UK
06:00 AM05:00 PM
Early Morning GMT
07:00 AM06:00 PM
Night Time
08:00 AM07:00 PM
Work Starts GMT
09:00 AM08:00 PM
Meeting Window
10:00 AM09:00 PM
Meeting Window
11:00 AM10:00 PM
GMT Afternoon

Greenwich Mean Time (GMT)

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

BST (UTC+1) from late March to late October

IANA Identifier:

Europe/London

Australian Eastern Standard Time (AEST)

UTC+10
UTC+11 during AEDT
Major Cities:
  • • Sydney
  • • Melbourne
  • • Brisbane
  • • Canberra
  • • Newcastle
Daylight Saving:

AEDT (UTC+11) from early October to early April (not in QLD)

IANA Identifier:

Australia/Sydney

Greenwich Mean Time (GMT) vs Australian Eastern Standard Time (AEST)

Greenwich Mean Time (GMT)Australian Eastern Standard Time (AEST)

Greenwich Mean Time (GMT) is the mean solar time at the Royal Observatory in Greenwich, London (UTC+0). During daylight saving time, the UK observes British Summer Time (BST), which is UTC+1.

Australian Eastern Standard Time (AEST) is 10 hours ahead of Coordinated Universal Time (UTC+10). During daylight saving time, the region observes Australian Eastern Daylight Time (AEDT), which is UTC+11.

Where Is It Used?

  • England: London, Manchester, Birmingham, Liverpool, Leeds
  • Scotland: Edinburgh, Glasgow, Aberdeen
  • Wales: Cardiff, Swansea, Newport
  • Northern Ireland: Belfast, Derry
  • Also Used In: Ireland, Portugal (mainland), Canary Islands, Morocco (seasonal)
  • New South Wales: Sydney, Newcastle, Wollongong, Central Coast
  • Victoria: Melbourne, Geelong, Ballarat
  • Queensland: Brisbane, Gold Coast, Sunshine Coast (no DST)
  • Australian Capital Territory: Canberra
  • Tasmania: Hobart, Launceston (observes AEDT)

Geographic Context

Prime Meridian

GMT is based on the Prime Meridian (0° longitude) which passes through the Royal Observatory in Greenwich, London. It is the historical basis for the world's time zones.

Global Influence

GMT is often used interchangeably with UTC, though technically GMT is a time zone while UTC is a time standard.

Eastern Australia

AEST covers Australia's eastern states where approximately 80% of Australia's population lives. It's one of three main time zones in Australia.

Queensland Exception

Queensland uses AEST year-round and does not observe daylight saving time, unlike NSW, VIC, ACT, and TAS.

Key Facts

  • UTC Offset: UTC+0 (GMT) / UTC+1 (BST)
  • Historical: Original reference for global timekeeping
  • Known For: Prime Meridian, Royal Observatory Greenwich
  • Largest City: London (9M metropolitan area)
  • DST Period: Last Sunday in March to last Sunday in October
  • Usage: UK, Ireland, Portugal, Canary Islands
  • UTC Offset: UTC+10 (AEST) / UTC+11 (AEDT)
  • Population: Covers ~80% of Australian population
  • Known For: Major economic and cultural centers of Australia
  • Largest City: Sydney (5.3M), Melbourne (5M)
  • DST Period: First Sunday in October to first Sunday in April
  • Note: Queensland does not observe DST

Quick Reference

Standard Difference: AEST is 10 hours ahead of GMT (can vary 9-11 hours with DST)
DST Variation: 9 hours when UK is BST and Australia is standard time; 11 hours when UK is GMT and Australia is AEDT
Distance: Approximately 10,500 miles (17,000 km) between London and Sydney
UTC Offsets: GMT = UTC+0, BST = UTC+1 | AEST = UTC+10, AEDT = UTC+11
Opposite Seasons: When it's summer in UK, it's winter in Australia and vice versa

Frequently Asked Questions

AEST (Australian Eastern Standard Time) is 10 hours ahead of GMT. However, this can vary between 9-11 hours depending on daylight saving transitions. When UK observes BST and Australia observes standard time, the difference is 9 hours. When UK observes GMT and Australia observes AEDT, the difference is 11 hours.

The best time to call from GMT to AEST is between 8:00 AM and 10:00 AM GMT, which corresponds to 6:00 PM to 8:00 PM AEST. This narrow window ensures GMT is within early business hours while AEST is in the evening, providing very limited but workable overlap.

Yes, the time difference varies because UK and Australia observe daylight saving at opposite times of the year. The standard difference is 10 hours (GMT to AEST). During UK summer (BST) while Australia is in standard time, it's 9 hours. During Australian summer (AEDT) while UK is in standard time, it's 11 hours.

GMT cities include London, Manchester, Birmingham, Liverpool, and Edinburgh. AEST cities include Sydney, Melbourne, Brisbane, Canberra, and Newcastle. These represent the most populous cities in the UK and eastern Australia.

In the UK, BST starts on the last Sunday in March and ends on the last Sunday in October. In Australia, AEDT starts on the first Sunday in October and ends on the first Sunday in April. Note that Brisbane (Queensland) does not observe daylight saving time.