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AST to GMT Time Converter

Use this AST to GMT time converter to compare Canada and United Kingdom time instantly. GMT is 4 hours ahead of AST, so 9:00 AM AST becomes 1:00 PM GMT and 5:00 PM AST becomes 9:00 PM GMT. The page is useful for business-hours overlap, international calls, remote-team handoffs, webinars, and travel planning, with daylight saving adjustments handled automatically.

AST Atlantic Standard Time
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GMT Greenwich Mean Time
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Select a time to convert

AST to GMT Quick Facts

Use this AST to GMT converter to compare Canada and United Kingdom time, check the 4 hours gap, and confirm the right slot for calls, handoffs, and deadlines. Good overlap starts around 9:00 AM AST / 1:00 PM GMT.

Time Difference
Greenwich Mean Time is 4 hours ahead of Atlantic Standard Time
Useful when deadlines, handoffs, or calls cross workday boundaries.
Best Call Window
Best overlap starts around 9:00 AM AST and 1:00 PM GMT.
Common Use Cases
Useful for remote teams, customer support windows, travel planning, webinars, and same-day deadline handoffs.

How to Convert AST to GMT

Converting between Atlantic Standard Time and Greenwich Mean Time means accounting for a 4 hours gap — here's how to do it in under 10 seconds with no sign-up.

Enter Your AST Time

Pick the date and time in Atlantic Standard Time (UTC -4) that you want to convert. Hit "Now" to load the current AST time instantly, or use "+1h" to step forward and compare.

Read the GMT Result

The equivalent Greenwich Mean Time (UTC +0) time appears immediately. Since GMT is 4 hours ahead of AST, most daytime conversions stay on the same calendar day.

Copy or Fine-Tune

Click "Copy Time" to grab the GMT result for your calendar or message. Use "+1d" to check how the conversion shifts across dates — useful when Daylight Saving Time changes the gap.

Why Choose Our AST to GMT Converter

Align AST–GMT Meetings Instantly

When someone in Canada suggests 9:00 AM AST, that's 1:00 PM GMT. This converter shows the overlap so both sides agree on one slot — no back-and-forth.

Spot Date-Line Shifts at a Glance

Late-night AST times can land on a different date in GMT because of the 4 hours offset. The converter labels "next day" or "previous day" next to the result so you never send a message a day early or miss a deadline.

Handles DST Transitions Automatically

Daylight Saving adjustments can widen or narrow the AST–GMT gap by an hour. During transition weeks many people get it wrong. This converter pulls the current UTC offsets automatically, so the result is right even on the changeover day.

Never Miss a AST-Timed Event

Product launches, sports matches, and webinars are often announced in AST. Convert the event time to GMT so you know exactly when to tune in — with a 4 hours difference, a morning event in Canada falls during work hours in Universal.

AST to GMT Time Conversion Chart

Quick-reference conversion table covering every hour of the day at a glance.

Complete 24-Hour Conversion

Atlantic Standard Time to Greenwich Mean Time full day schedule

12:00 AM
AST
4:00 AM
GMT
1:00 AM
AST
5:00 AM
GMT
2:00 AM
AST
6:00 AM
GMT
3:00 AM
AST
7:00 AM
GMT
4:00 AM
AST
8:00 AM
GMT
5:00 AM
AST
9:00 AM
GMT
6:00 AM
AST
10:00 AM
GMT
7:00 AM
AST
11:00 AM
GMT
8:00 AM
AST
12:00 PM
GMT
9:00 AM
AST
1:00 PM
GMT
10:00 AM
AST
2:00 PM
GMT
11:00 AM
AST
3:00 PM
GMT
12:00 PM
AST
4:00 PM
GMT
1:00 PM
AST
5:00 PM
GMT
2:00 PM
AST
6:00 PM
GMT
3:00 PM
AST
7:00 PM
GMT
4:00 PM
AST
8:00 PM
GMT
5:00 PM
AST
9:00 PM
GMT
6:00 PM
AST
10:00 PM
GMT
7:00 PM
AST
11:00 PM
GMT
8:00 PM
AST
12:00 AM
GMT
(next day)
9:00 PM
AST
1:00 AM
GMT
(next day)
10:00 PM
AST
2:00 AM
GMT
(next day)
11:00 PM
AST
3:00 AM
GMT
(next day)