Seoul to Hagåtña Time
KST to ChST Converter — 9 AM KST is 10:00 AM ChST
Seoul is 1 hour behind Hagåtña. Convert any time between Seoul (KST) and Hagåtña (ChST) instantly.
Seoul
South Korea
Hagåtña
Guam
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Time Zone Comparison
Seoul to Hagåtña Time Conversion Table
| Seoul (KST) | Hagåtña (ChST) |
|---|---|
| 12:00 AM | 1:00 AM |
| 2:00 AM | 3:00 AM |
| 4:00 AM | 5:00 AM |
| 6:00 AM | 7:00 AM |
| 8:00 AM | 9:00 AM |
| 10:00 AM | 11:00 AM |
| 12:00 PM | 1:00 PM |
| 2:00 PM | 3:00 PM |
| 4:00 PM | 5:00 PM |
| 6:00 PM | 7:00 PM |
| 8:00 PM | 9:00 PM |
| 10:00 PM | 11:00 PM |
Seoul & Hagåtña — Business & Scheduling Guide
Seoul is a global tech and cultural powerhouse, known for Samsung, LG, K-pop, e-sports, semiconductors, and 5G leadership. Hagåtña (Guam) is a US territory and strategic Pacific military base, known for US military, tourism, construction, and fishing. With a 1-hour time difference, professionals frequently schedule cross-border calls between these two cities for international trade, remote team collaboration, and client meetings.
Scheduling Meetings Between Seoul and Hagåtña
With only a 1-hour gap, Seoul and Hagåtña have generous overlapping work hours. Morning calls in the later time zone align well with mid-day in the other. South Korean work culture is fast-paced with typical hours of 9 AM–6 PM, though recent reforms have reduced maximum weekly hours. Guam business hours are typically 8 AM–5 PM, with a US-style business environment. Most teams find that late morning to early afternoon offers the widest window for collaboration.
Daylight Saving Time Considerations
Neither Seoul nor Hagåtña observes Daylight Saving Time — Seoul stays on KST and Hagåtña stays on ChST year-round. This makes scheduling between these two cities simpler, as the 1-hour time difference remains constant throughout the year with no DST surprises.
Collaboration Tools & Workflow
Teams working between Seoul and Hagåtña enjoy strong real-time collaboration potential. With just a 1-hour time difference, daily standups, pair programming, and spontaneous video calls are all practical. Popular tools for Seoul–Hagåtña teams include Slack for real-time messaging, Google Meet or Zoom for video calls, and Notion or Linear for project management. The overlapping work window is wide enough that most teams can operate nearly synchronously.
Remote Work Between Seoul & Hagåtña
Seoul, Samsung, and Hagåtña, a key city in Guam, are well-connected for remote work. With a manageable 1-hour time difference, distributed teams can maintain a near-synchronous workflow. Both cities have strong internet infrastructure, coworking spaces, and established remote work cultures. For freelancers and remote workers, this time zone pairing is ideal — you can serve clients in Hagåtña from Seoul (or vice versa) without disrupting your standard workday.
KST to ChST — Quick Reference
KST (KST) stands for the timezone used in Seoul, South Korea (UTC+9). ChST (ChST) is the timezone used in Hagåtña, Guam (UTC+10). Seoul is 1 hour behind Hagåtña.
To convert KST to ChST, add 1 hours to KST time. For example, KST 9:00 AM = ChST 10:00 AM.
Key Facts
- •Time difference: Seoul (UTC+9) is 1 hour behind Hagåtña (UTC+10).
- •Daylight Saving Time: Seoul does not observe DST (KST). Hagåtña does not observe DST (ChST).
- •Regions: Seoul is located in South Korea and uses the KST time zone. Hagåtña is located in Guam and uses the ChST time zone.
- •Best time to call: The best time to call between Seoul and Hagåtña is 9:00 AM to 3:00 PM in Seoul time, when both cities have overlapping standard working hours.
Frequently Asked Questions
What is the time difference between Seoul and Hagåtña?
Seoul is 1 hour behind Hagåtña.
What time is it in Hagåtña when it's 9 AM in Seoul?
When it's 9:00 AM in Seoul, it is 10:00 AM in Hagåtña.
What time is 9 PM KST in ChST?
9 PM KST (Seoul time) is 10:00 PM ChST (Hagåtña time). This is a common time people check when scheduling evening calls across these two time zones.
When is the best time to schedule a meeting between Seoul and Hagåtña?
The best time to schedule a meeting is between 9:00 AM to 3:00 PM in Seoul time, when both cities are within standard working hours (9 AM – 5 PM). This gives you the maximum overlap window for real-time collaboration.
How do I convert KST to ChST?
KST (KST) is the timezone for Seoul, South Korea (UTC+9). ChST (ChST) is the timezone for Hagåtña, Guam (UTC+10). Seoul is 1 hour behind Hagåtña. Quick examples: 9 AM KST = 10:00 AM ChST, 12 PM KST = 1:00 PM ChST, 3 PM KST = 4:00 PM ChST, 6 PM KST = 7:00 PM ChST.
Is Seoul ahead of or behind Hagåtña?
Seoul is 1 hour behind Hagåtña. When it's noon in Seoul, it's 1:00 PM in Hagåtña.
Does Seoul or Hagåtña change clocks for Daylight Saving Time?
No, Seoul does not observe DST — it stays on KST year-round. Hagåtña does not observe DST — it stays on ChST year-round.
What time is noon in Seoul in Hagåtña time?
When it is 12:00 PM (noon) in Seoul (KST), it is 1:00 PM in Hagåtña (ChST). This is often a popular time for scheduling lunch-hour calls across the Seoul–Hagåtña corridor.
What are the overlapping work hours between Seoul and Hagåtña?
The overlapping work hours between Seoul and Hagåtña are approximately 9:00 AM to 3:00 PM in Seoul time, when both cities are within the standard 9 AM–5 PM workday. This is the ideal window for meetings, pair programming, and real-time collaboration.
What timezone is Seoul in?
Seoul is in the KST time zone (UTC+9). It is located in South Korea. Seoul does not observe Daylight Saving Time.
What timezone is Hagåtña in?
Hagåtña is in the ChST time zone (UTC+10). It is located in Guam. Hagåtña does not observe Daylight Saving Time.
How do I schedule a call between Seoul and Hagåtña?
To schedule a call between Seoul and Hagåtña, aim for the overlapping window of 9:00 AM to 3:00 PM in Seoul time. Use Google Calendar or Calendly with both time zones visible, share the meeting invite with the ChST time clearly noted, and always double-check the time difference — especially during DST transitions. Pro tip: include both local times in the calendar invite title (e.g., "Sync — 10 AM KST / 11:00 AM ChST").
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