Convert GMT to KST
See the 9-hour difference from GMT to Korea Standard Time, compare times by hour, and schedule meetings with calendar export tools.
How to Convert GMT to KST
Open the GMT to KST converter: Go to https://www.xconvert.com/time-converter/gmt-to-kst-converter. The page loads with GMT and KST already set up in the comparison grid, which is useful if you are scheduling a call between London-based partners using Greenwich Mean Time and teams in South Korea working on Korea Standard Time, such as electronics, gaming, shipping, or manufacturing operations in Seoul.
Add comparison cities if your schedule involves more regions: Click “+ Add City” and add places such as London, Seoul, Singapore, or New York depending on your workflow. This is especially practical for companies coordinating UK headquarters, Korean suppliers, and Asia-Pacific sales teams, because you can see whether a GMT morning overlaps with Seoul office hours while also checking if another market is still asleep.
Drag across the grid to select the meeting window: Click “Select” if needed, then drag on the GMT row from 9:00 AM to 11:00 AM GMT to highlight that range in purple. The KST row will show the same period as 6:00 PM to 8:00 PM KST, which helps confirm that a late-afternoon or early-evening meeting in Korea works better than a Korean morning meeting, since 9:00 AM KST is 12:00 AM GMT the same day.
Export and share the confirmed time: Once the purple selection is visible, use the export options for ICS download, Google Calendar, Gmail, Copy to clipboard, or Share link. This is useful when sending a confirmed meeting slot to a UK client and a Seoul product team, because the calendar export automatically places the event in each participant’s local time zone and reduces mistakes around the 9-hour offset.
Understanding the GMT to KST Time Difference
Korea Standard Time is 9 hours ahead of Greenwich Mean Time. That means 12:00 PM GMT = 9:00 PM KST, and 9:00 AM GMT = 6:00 PM KST on the same calendar day. If it is 8:00 AM in GMT, it is already 5:00 PM in South Korea, which is why same-day collaboration usually favors the GMT morning.
KST is fixed at UTC+9 all year, and South Korea does not observe daylight saving time. GMT is UTC+0, also without daylight saving when it is specifically labeled GMT, so the difference between GMT and KST stays exactly 9 hours in every month, including January, April, July, and October. There are no seasonal weeks when the GMT-to-KST gap becomes 8 or 10 hours, unlike comparisons involving British Summer Time or U.S. daylight saving zones.
This distinction matters because many users confuse GMT with UK local time. In the United Kingdom, civil time changes to British Summer Time (BST, UTC+1) from the last Sunday in March to the last Sunday in October, so if someone actually means London summer time rather than true GMT, the difference to KST becomes 8 hours instead of 9 during that period. For example, 9:00 AM London time in July is 5:00 PM KST, while 9:00 AM GMT would be 6:00 PM KST.
Best Times for Calls and Meetings Between GMT and KST
The most practical overlap for standard office hours is usually the GMT morning and KST late afternoon to early evening. A strong working window is 8:00 AM-10:00 AM GMT = 5:00 PM-7:00 PM KST, which often works for UK-based operations, logistics teams, financial reporting, and supplier check-ins with Seoul before Korean offices close.
Another commonly used slot is 9:00 AM-11:00 AM GMT = 6:00 PM-8:00 PM KST. This is often the best compromise for remote product teams, software vendors, semiconductor partners, and e-commerce businesses that need real-time discussion without forcing the GMT side into an early pre-work call or the KST side into a very late night meeting.
If the Korean team can start early, 12:00 AM-2:00 AM GMT = 9:00 AM-11:00 AM KST creates a Korean morning window, but this is usually unrealistic for people actually working on GMT because it falls just after midnight. For that reason, most business meetings between GMT and KST are scheduled from early to late morning GMT, which translates into late afternoon or evening in Korea.
For recurring meetings, 7:00 AM GMT = 4:00 PM KST can be a useful compromise for multinational operations with long agendas, because it keeps the Korean side within regular office hours and still lands at the beginning of the GMT workday. By contrast, 1:00 PM GMT = 10:00 PM KST, so afternoon meetings in GMT are generally too late for Seoul unless the Korean participants are in customer support, gaming operations, media, or another industry that regularly runs evening shifts.
Frequently Asked Questions
What is the time difference between GMT and KST?
KST is 9 hours ahead of GMT year-round. If it is 10:00 AM GMT, it is 7:00 PM KST the same day; if it is 3:00 PM GMT, it is 12:00 AM KST the next day. Because KST is UTC+9 and GMT is UTC+0, the offset is stable and easy to calculate by adding 9 hours.
When is 9 AM GMT in KST?
9:00 AM GMT is 6:00 PM KST on the same calendar day. This is one of the most practical conversion points for business users because it places the meeting in the Korean early evening, which is still possible for many office teams in Seoul, Incheon, or Suwon.
Does the difference between GMT and KST change during DST?
No, the difference between GMT and KST stays 9 hours all year. South Korea does not use daylight saving time, and GMT itself is a fixed UTC+0 standard. Confusion usually happens when people really mean UK local time, because the UK shifts to BST (UTC+1) from the last Sunday in March to the last Sunday in October, which changes the London-to-KST difference to 8 hours during that season.
What is the best meeting time between GMT and KST?
The best meeting window is usually 8:00 AM-11:00 AM GMT, which corresponds to 5:00 PM-8:00 PM KST. This range gives the GMT side a normal morning slot and keeps the Korean side within late office hours or early evening, which is commonly acceptable for technology, trade, shipping, and cross-border vendor meetings.
Is KST always the same as Seoul time?
Yes, Seoul time is KST, and KST is used throughout South Korea at UTC+9. Unlike countries with multiple time zones, South Korea uses one national standard time, so a meeting set for 3:00 PM KST is the same in Seoul, Busan, Incheon, Daegu, and Daejeon.
How do I quickly convert GMT to KST without doing the math manually?
Use the visual grid on the GMT to KST converter page and drag across the GMT row to highlight the time you are considering. The KST row updates instantly to show the corresponding Korean time, and you can then export the result through ICS, Google Calendar, Gmail, Copy to clipboard, or Share link for teammates who need the meeting in their own local calendar.
Why do GMT afternoon meetings often not work well for South Korea?
Because KST is 9 hours ahead, a 2:00 PM GMT meeting becomes 11:00 PM KST the same day. That is too late for most standard office schedules in South Korea, so teams usually avoid GMT afternoon calls unless the Korean participants work in industries with extended hours, such as live operations, international customer support, or media production.