KST to AST Converter
AST is 13 hours behind KST
KST to AST Conversion Table
Green rows indicate standard business hours (9 AM – 5 PM) in AST
| KST | AST |
|---|---|
| 12:00 AM | 11:00 AM -1d |
| 1:00 AM | 12:00 PM -1d |
| 2:00 AM | 1:00 PM -1d |
| 3:00 AM | 2:00 PM -1d |
| 4:00 AM | 3:00 PM -1d |
| 5:00 AM | 4:00 PM -1d |
| 6:00 AM | 5:00 PM -1d |
| 7:00 AM | 6:00 PM -1d |
| 8:00 AM | 7:00 PM -1d |
| 9:00 AM | 8:00 PM -1d |
| 10:00 AM | 9:00 PM -1d |
| 11:00 AM | 10:00 PM -1d |
| 12:00 PM | 11:00 PM -1d |
| 1:00 PM | 12:00 AM |
| 2:00 PM | 1:00 AM |
| 3:00 PM | 2:00 AM |
| 4:00 PM | 3:00 AM |
| 5:00 PM | 4:00 AM |
| 6:00 PM | 5:00 AM |
| 7:00 PM | 6:00 AM |
| 8:00 PM | 7:00 AM |
| 9:00 PM | 8:00 AM |
| 10:00 PM | 9:00 AM |
| 11:00 PM | 10:00 AM |
Converting Korea Standard Time to Atlantic Standard Time
Korea Standard Time (KST) and Atlantic Standard Time (AST) are separated by a 13 hours time difference. AST is 13 hours behind KST. KST is UTC+9, used in South Korea, while AST is UTC-4, used in Canada, Puerto Rico, US Virgin Islands.
When converting from KST to AST, the key reference points to remember are: 9:00 AM KST equals 8:00 PM AST, 12:00 PM noon KST equals 11:00 PM AST, and 5:00 PM KST equals 4:00 AM AST. The conversion table above shows every hour of the day mapped between these two time zones.
Scheduling Across KST and AST
For professionals scheduling meetings between KST and AST, finding overlapping business hours is essential. Standard business hours are typically 9:00 AM to 5:00 PM in each time zone. Given the 13 hours difference, the window of overlap may be limited, making early morning or late evening calls necessary for one party. Use the highlighted working hours in the conversion table above to quickly identify suitable meeting times.
Daylight Saving Time Considerations
KST does not observe Daylight Saving Time, maintaining UTC+9 year-round. AST observes DST, switching to ADT (UTC-3). During DST transitions, the time difference between these zones may temporarily change by 1 hour. Always verify the current offset during spring and fall transition periods.