GMT to AST Time Converter
About this conversion
AST here means Atlantic Standard Time (UTC-4), used in Puerto Rico, Bermuda in winter and Atlantic Canada. The same abbreviation also stands for Arabia Standard Time (UTC+3), so it is one of the most ambiguous time zone abbreviations.
When the time difference changes
Both sides keep a fixed offset, so the gap does not change in the next two years.
Best time to call or meet
13:00 to 17:00 GMT is 09:00 to 13:00 AST, 4 hours of shared 09:00 to 17:00 time.
Common times
- 06:00 GMT = 02:00 AST
- 09:00 GMT = 05:00 AST
- 12:00 GMT = 08:00 AST
- 15:00 GMT = 11:00 AST
- 17:00 GMT = 13:00 AST
- 20:00 GMT = 16:00 AST
GMT to AST hour-by-hour table
Highlighted rows fall within 09:00 to 17:00 on both sides.
| GMT | AST |
|---|---|
| 00:00 | 20:00 (previous day) |
| 01:00 | 21:00 (previous day) |
| 02:00 | 22:00 (previous day) |
| 03:00 | 23:00 (previous day) |
| 04:00 | 00:00 |
| 05:00 | 01:00 |
| 06:00 | 02:00 |
| 07:00 | 03:00 |
| 08:00 | 04:00 |
| 09:00 | 05:00 |
| 10:00 | 06:00 |
| 11:00 | 07:00 |
| 12:00 | 08:00 |
| 13:00 | 09:00 |
| 14:00 | 10:00 |
| 15:00 | 11:00 |
| 16:00 | 12:00 |
| 17:00 | 13:00 |
| 18:00 | 14:00 |
| 19:00 | 15:00 |
| 20:00 | 16:00 |
| 21:00 | 17:00 |
| 22:00 | 18:00 |
| 23:00 | 19:00 |
Related conversions
Clock change guides
- What Is Daylight Saving Time (DST)? A Plain-English GuideWhat daylight saving time is, how it works in the UK, Europe and the US, why it exists, its history, who uses it and the argument over scrapping it.
- Why Do the Clocks Go Back in October? The Real ReasonThe clocks go back in autumn to return the UK to GMT, so winter mornings are lighter. The history, the rule, what time it happens and what changes for you.
- When Do the Clocks Go Forward Again After Going Back?When the UK clocks go forward again after the autumn change, how long the UK stays on GMT, when evenings get lighter and how to remember to reset your clocks.
Frequently asked questions
What is 15:00 GMT in AST?
15:00 GMT is 11:00 AST at the moment. The answer can change by an hour when either side changes its clocks.
What are the shared working hours for GMT and AST?
13:00 to 17:00 GMT is 09:00 to 13:00 AST, 4 hours of shared 09:00 to 17:00 time.
When does the GMT to AST time difference change?
It does not change in the next two years.