London
Sydney
Convert GMT to AEST
Greenwich Mean Time to Australian Eastern Standard Time — Sydney is 9 hours ahead of London
Quick Facts
Time Difference
+9 hours
GMT Full Name
Greenwich Mean Time
AEST Full Name
Australian Eastern Standard Time
GMT to AEST Conversion Table
Related Conversions
About GMT and AEST Time Zones
GMT (Greenwich Mean Time) is UTC+0 and covers cities like London, Dublin, Lisbon. AEST (Australian Eastern Standard Time) is UTC+10 and covers cities like Sydney, Melbourne, Brisbane.
When it's 12:00 PM (noon) in London (GMT), it's 9:00 PM in Sydney (AEST). The time difference between GMT and AEST is 9 hours — Sydney is ahead of London.
The 10-hour difference makes real-time overlap challenging — early morning calls (7–9 AM GMT) work best.
Daylight Saving Time
AEST observes Daylight Saving Time and becomes AEDT (Australian Eastern Daylight Time) during summer months, shifting clocks forward by 1 hour to UTC+11.
During DST transitions, the time difference between GMT and AEST may shift by ±1 hour. Always verify the current offset above for the most accurate conversion.
Use our world clock tool to compare London and Sydney with a visual timeline, or browse more timezone conversions.
Frequently Asked Questions
What is the time difference between GMT and AEST?
Sydney (AEST) is 9 hours ahead of London (GMT). The offset is +9 hours.
Is AEST ahead or behind GMT?
AEST is 9 hours ahead of GMT. GMT is UTC+1 and AEST is UTC+10.
When it's 12:00 PM in London, what time is it in Sydney?
When it's 12:00 PM (noon) in London (GMT), it's 9:00 PM in Sydney (AEST).
When it's 5:00 PM in London, what time is it in Sydney?
When it's 5:00 PM in London (GMT), it's 2:00 AM in Sydney (AEST).
Does AEST change for Daylight Saving Time?
Yes. AEST (Australian Eastern Standard Time, UTC+10) becomes AEDT (Australian Eastern Daylight Time, UTC+11) in summer, shifting clocks forward 1 hour.