The short answer

12pm in Mountain Standard Time is 4am in Australian Eastern Standard Time on the next day.

Mountain Standard Time is 16 hours behind Australian Eastern Standard Time. It lands deep outside working hours in Australian Eastern Standard Time — see the best time to meet below for a friendlier slot.

Mountain Standard Time
12pm
Australian Eastern Standard Time
4am
next day
Right now
2:59pmMDT · UTC-06:00 · Wed, Jun 24
6:59amAEST · UTC+10:00 · Thu, Jun 25
Read across to convert
Mountain Standard Time
MDT · UTC-06:00
2:59pm ☀
Australian Eastern Standard Time
AEST · UTC+10:00
6:59am ☀
Pinned12pmMountain Standard Time=4amAustralian Eastern Standard Time · Thu (next day)
12amWed
4pm
WORK
1am
5pm
2am
6pm
3am
7pm
4am
8pm
5am
9pm
6am
10pm
7am
11pm
8am
12amThu ·+1d
9am
WORK
1amThu ·+1d
10am
WORK
2amThu ·+1d
11am
WORK
3amThu ·+1d
PINNED
12pm
WORK
4amThu ·+1d
1pm
WORK
5amThu ·+1d
NOW
2pm
WORK
6amThu ·+1d
3pm
WORK
7amThu ·+1d
4pm
WORK
8amThu ·+1d
5pm
9amThu ·+1d
WORK
6pm
10amThu ·+1d
WORK
7pm
11amThu ·+1d
WORK
8pm
12pmThu ·+1d
WORK
9pm
1pmThu ·+1d
WORK
10pm
2pmThu ·+1d
WORK
11pm
3pmThu ·+1d
WORK
daylightnightworking hoursoverlap
Best time to meet
Closest workable window
Just outside the working window — early on one side, late on the other.
Mountain Standard Time
3pm–7pm
=
Australian Eastern Standard Time
7am–11am
next day
Popular conversions

Quick reference.

9amMountain Standard Time=1amAustralian Eastern Standard Time · next day
12pmMountain Standard Time=4amAustralian Eastern Standard Time · next day
3pmMountain Standard Time=7amAustralian Eastern Standard Time · next day
5pmMountain Standard Time=9amAustralian Eastern Standard Time · next day
9pmMountain Standard Time=1pmAustralian Eastern Standard Time · next day
In context

What each side covers.

Mountain Standard Time
MDT · UTC-06:00
2:59pm
Cities on this clock
6:59am
Cities on this clock

Frequently asked

Quick answers about converting between Mountain Standard Time and Australian Eastern Standard Time. Can't find what you need? Email [email protected].

What is the time difference between Mountain Standard Time and Australian Eastern Standard Time?
Mountain Standard Time is 16 hours behind Australian Eastern Standard Time right now. We always show the live, daylight-saving-correct difference, so this figure already accounts for whichever side is observing summer time today.
When it's 12pm in Mountain Standard Time, what time is it in Australian Eastern Standard Time?
12pm in Mountain Standard Time is 4am in Australian Eastern Standard Time on the next day. It lands deep outside working hours in Australian Eastern Standard Time — see the best time to meet below for a friendlier slot. Use the hour-by-hour table above to read any other time across.
What's the best time for a call between Mountain Standard Time and Australian Eastern Standard Time?
There's no comfortable 9-to-5 overlap between Mountain Standard Time and Australian Eastern Standard Time — they sit on opposite sides of the planet's working day. Plan for an early or late call on one side, or hand work off asynchronously.
Does this account for daylight saving time?
Yes. We track every clock change in both places, so the abbreviations you see — MDT and AEST — are the ones actually in effect right now, not a fixed all-year value. When either side changes its clocks, this page updates automatically.
Why is the date sometimes different on each side?
When two places are far enough apart, the same moment can fall on different calendar days. That is why some conversions are marked "previous day" or "next day" — it is the same instant in time, read off two clocks that crossed midnight at different points.