AST GMTTime Converter
AST (UTC−4) is currently 4 hours behind GMT (UTC±0). Compare live clocks, convert any hour, and find times to meet.
Best time to meet between AST and GMT
Best meeting times:
AST: 9:00 AM – 2:00 PM
GMT: 1:00 PM – 6:00 PM
Quick answer
When it's in AST, it's the same day in GMT.
AST runs 4 hours behind GMT. Both sides keep standard office hours with a real 9–6 overlap: the highlighted window above works for everyone.
- Time difference
- +4h 00m
- AST
- UTC−4
- GMT
- UTC±0
- Best call window
- 9:00 AM AST
AST to GMT conversion table
The next 12 hours in AST and the matching local time in GMT. The current hour is highlighted; drag the converter's slider and the table follows.
| AST | GMT |
|---|---|
| NOW Thu, Aug 6 |
Thu, Aug 6 |
Thu, Aug 6 |
Fri, Aug 7 |
Thu, Aug 6 |
Fri, Aug 7 |
Thu, Aug 6 |
Fri, Aug 7 |
Thu, Aug 6 |
Fri, Aug 7 |
Fri, Aug 7 |
Fri, Aug 7 |
Fri, Aug 7 |
Fri, Aug 7 |
Fri, Aug 7 |
Fri, Aug 7 |
Fri, Aug 7 |
Fri, Aug 7 |
Fri, Aug 7 |
Fri, Aug 7 |
Fri, Aug 7 |
Fri, Aug 7 |
Fri, Aug 7 |
Fri, Aug 7 |
Daylight saving shifts this gap by up to 1 hour
The difference between AST and GMT swings between 3 and 4 hours across the year as each side starts or ends daylight saving. Regions on AST switch to ADT (UTC−3) during daylight saving time. Regions on GMT switch to BST (UTC+1) during daylight saving time. This page always shows the live, DST-aware difference.
Related time zone conversions
Jump straight to another pair: every combination is a live tool, not an article.
From AST
To GMT
One source of truth, for you and your AI
This page exposes the same answer as structured data, so when you ask an assistant "what's 9am AST time in GMT?", it can cite the exact, DST-aware result, not a stale blog post.
- Schema.org JSON-LD on every converter page
- A machine-readable facts island with time zone identifiers and every possible offset
- Live times in <time datetime> elements with explicit UTC offsets
{
"pair": "AST → GMT",
"url": "https://worldclock.pro/en/convert/ast-to-gmt",
"from": {
"name": "AST",
"type": "timezone",
"abbreviation": "AST",
"daylightAbbreviation": "ADT",
"iana": "America/Halifax",
"standardUtcOffset": "-04:00",
"daylightUtcOffset": "-03:00",
"referenceCity": "Halifax"
},
"to": {
"name": "GMT",
"type": "timezone",
"abbreviation": "GMT",
"daylightAbbreviation": "BST",
"iana": "Europe/London",
"standardUtcOffset": "+00:00",
"daylightUtcOffset": "+01:00",
"referenceCity": "London"
},
"currentDifferenceMinutes": 240,
"possibleDifferencesMinutes": [
180,
240
],
"note": "Between the regions that use these zones the difference is 3 and 4 hours across the year, depending on daylight saving on each side. The clocks on this page show the named zones themselves, which are fixed."
}
Frequently asked questions
What is the time difference between AST and GMT?
AST is currently 4 hours behind GMT. AST is on AST (UTC−4) and GMT is on GMT (UTC±0). The difference can change when either side starts or ends daylight saving time.
Is GMT ahead of or behind AST?
GMT is currently 4 hours ahead of AST.
When it is 9:00 AM in AST, what time is it in GMT?
When it is 9:00 AM on a Thursday in AST, it is 1:00 PM in GMT.
Do AST and GMT observe daylight saving time?
Regions on AST switch to ADT (UTC−3) during daylight saving time. Regions on GMT switch to BST (UTC+1) during daylight saving time.
How do I convert AST time to GMT time?
Add 4 hours to any time in AST to get the time in GMT. This page's converter and 24-hour table do it automatically and stay correct through daylight-saving changes.
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