Convert Atlantic Time to Greenwich Mean Time
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AST · UTC−4 → GMT · UTC+0
AST is 4 hours behind GMT
Halifax · ADT
Wednesday, 7 October 2026
London · BST
Wednesday, 7 October 2026
When are both sides at work?Each column is one hour of the day in the first city; the second row shows the same moment in the other city. Gold means office hours (09:00–18:00), dusk means awake but off work, night means asleep (23:00–07:00). Columns where both rows are gold are good meeting times.
Shared working hours: 09:00–14:00 in Halifax is 13:00–18:00 in London.
Working (09–18) Awake, off the clock Asleep (23–07)
Pick a time and share it
08:24 Wed 7 Oct Halifax = 12:24 Wed 7 Oct London
Hour-by-hour conversion
| Halifax (AST)Every hour of today in the first city, with the matching time in the second. “Next day” means the calendar date is already tomorrow there. The highlighted row is right now. | London (GMT) | |
|---|---|---|
| 00:00 | 04:00 | |
| 01:00 | 05:00 | |
| 02:00 | 06:00 | |
| 03:00 | 07:00 | |
| 04:00 | 08:00 | |
| 05:00 | 09:00 | |
| 06:00 | 10:00 | |
| 07:00 | 11:00 | |
| 08:00 | 12:00 | Now |
| 09:00 | 13:00 | Both at work |
| 10:00 | 14:00 | Both at work |
| 11:00 | 15:00 | Both at work |
| 12:00 | 16:00 | Both at work |
| 13:00 | 17:00 | Both at work |
| 14:00 | 18:00 | |
| 15:00 | 19:00 | |
| 16:00 | 20:00 | |
| 17:00 | 21:00 | |
| 18:00 | 22:00 | |
| 19:00 | 23:00 | |
| 20:00 | 00:00next day | |
| 21:00 | 01:00next day | |
| 22:00 | 02:00next day | |
| 23:00 | 03:00next day |
About this conversion
AST here means Atlantic Time, represented by Halifax (America/Halifax), currently UTC−3. GMT means Greenwich Mean Time, represented by London (Europe/London), currently UTC+1.
AST is used by 32 zones, including Canada. If you meant a different one, see every meaning of AST.
GMT is used by 22 zones, including United Kingdom. See every meaning of GMT.
Working hours are shown as 09:00–18:00 local, and sleeping hours as 23:00–07:00. The hour table is anchored on the current day in Halifax; day boundaries are marked where the date differs.
Quick answers
- 09:00 AST is 13:00 GMT
- 12:00 AST is 16:00 GMT
- 15:00 AST is 19:00 GMT
- 18:00 AST is 22:00 GMT
Related conversions
- Atlantic Time to Mexican Pacific TimeAST → GMT-7
- Atlantic Time to Gulf TimeAST → GST
- Atlantic Time to Iran TimeAST → IRST
- Atlantic Time to Peru TimeAST → PET
- Australian Western Time to Greenwich Mean TimeAWST → GMT
- Azerbaijan Time to Greenwich Mean TimeAZT → GMT
- Cocos Islands Time to Greenwich Mean TimeCCT → GMT
- French Guiana Time to Greenwich Mean TimeGFT → GMT
- Atlantic Time to India TimeAST → IST
- Greenwich Mean Time to India TimeGMT → IST
- Time in Halifaxnow, DST, offset
- Time in Londonnow, DST, offset