AST to KST Converter & Meeting Planner
Quick answer: 9:00 AM AST = 10:00 PM KST (fixed -04:00 standard offset — not DST-adjusted). Use the interactive converter below for DST-aware local-time scheduling.
Planning a call or meeting between Atlantic Standard Time (AST) and Korea Standard Time (KST)? You need to account for the standard time difference. Korea Standard Time is normally 13 hours ahead of Atlantic Standard Time. Whether you are coordinating between teams in Halifax and San Juan and Seoul and Busan, our live tool has you covered. Use our interactive overlap studio below to find the perfect waking hours for both regions, taking into account any seasonal Daylight Saving Time (DST) changes.
24-Hour Conversion Table
Quick reference: 12:00 AM AST = 1:00 PM KST. The full 24-hour AST to KST table below uses fixed standard offsets for exact abbreviation searches.
Example: 3:00 PM AST = 4:00 AM KST (+1 day).
| AST Time | KST Time |
|---|---|
| 12:00 AM (00:00) | 1:00 PM (13:00) |
| 1:00 AM (01:00) | 2:00 PM (14:00) |
| 2:00 AM (02:00) | 3:00 PM (15:00) |
| 3:00 AM (03:00) | 4:00 PM (16:00) |
| 4:00 AM (04:00) | 5:00 PM (17:00) |
| 5:00 AM (05:00) | 6:00 PM (18:00) |
| 6:00 AM (06:00) | 7:00 PM (19:00) |
| 7:00 AM (07:00) | 8:00 PM (20:00) |
| 8:00 AM (08:00) | 9:00 PM (21:00) |
| 9:00 AM (09:00) | 10:00 PM (22:00) |
| 10:00 AM (10:00) | 11:00 PM (23:00) |
| 11:00 AM (11:00) | 12:00 AM (00:00)+1 day |
| 12:00 PM (12:00) | 1:00 AM (01:00)+1 day |
| 1:00 PM (13:00) | 2:00 AM (02:00)+1 day |
| 2:00 PM (14:00) | 3:00 AM (03:00)+1 day |
| 3:00 PM (15:00) | 4:00 AM (04:00)+1 day |
| 4:00 PM (16:00) | 5:00 AM (05:00)+1 day |
| 5:00 PM (17:00) | 6:00 AM (06:00)+1 day |
| 6:00 PM (18:00) | 7:00 AM (07:00)+1 day |
| 7:00 PM (19:00) | 8:00 AM (08:00)+1 day |
| 8:00 PM (20:00) | 9:00 AM (09:00)+1 day |
| 9:00 PM (21:00) | 10:00 AM (10:00)+1 day |
| 10:00 PM (22:00) | 11:00 AM (11:00)+1 day |
| 11:00 PM (23:00) | 12:00 PM (12:00)+1 day |
Best time to call Seoul from Halifax
For most work calls, compare the normal business day in Halifax (AST) with the business day in Seoul (KST). AST commonly covers North America, Caribbean, while KST is mainly associated with East Asia.
⚠️ Note: 2026-07-05 is not a normal workday in one or both regions based on their configured calendar. The overlap below should be treated as a reference, not a guaranteed office-hours window.
⚠️ There is no clean same-day business-hours overlap on 2026-07-05. A practical compromise is around 9:00 PM AST, which reaches 9:00 AM KST near the start of their workday.
- DST Safety: AST or KST may shift during Daylight Saving Time. Always confirm the converted time for your specific date.
- Korea Exchange (KRX): 09:00-15:30 local time in Seoul.
🔥 Popular AST & KST Converters
Frequently searched time zone conversions related to your search.
Related Time Converters
Explore nearby time zone offsets and reverse conversions related to AST and KST.
Frequently Asked Questions
What is the time difference between AST and KST?
During standard time, Korea Standard Time is 13 hours ahead of Atlantic Standard Time.
Does the Caribbean observe Daylight Saving Time?
The vast majority of Caribbean nations and territories — including Puerto Rico, the Dominican Republic, the US Virgin Islands, Trinidad and Tobago, and Barbados — do not observe Daylight Saving Time and remain on AST (UTC-4) year-round. This means these territories share the same clock as Halifax only during the Atlantic Standard Time window in winter, diverging by one hour once Canada and Bermuda advance to ADT each spring.
What is the difference between AST and ADT?
AST (Atlantic Standard Time) is the standard winter offset at UTC-4:00, observed from the first Sunday in November through the second Sunday in March across all AST regions. ADT (Atlantic Daylight Time) is the summer offset at UTC-3:00, applied by Eastern Canadian provinces and Bermuda when they advance their clocks by one hour during Daylight Saving Time.
Does South Korea observe Daylight Saving Time?
South Korea does not observe Daylight Saving Time and has not done so since 1988, when DST was discontinued following the Seoul Summer Olympics. KST remains fixed at UTC+9:00 every day of the year, meaning the offset between Seoul and any DST-observing country shifts by one hour twice annually when those countries change their clocks.
Are KST and JST the same?
Yes, Korea Standard Time (KST) and Japan Standard Time (JST) share the identical UTC+9:00 offset, and neither country observes Daylight Saving Time. Seoul and Tokyo run on exactly the same clock year-round, which directly supports the deep semiconductor, automotive, and consumer electronics supply chain integration between the two economies.