Compare GMT vs KST
See the 9-hour difference between GMT and KST, check current local times, and find practical meeting hours across the UK and South Korea.
How to Find the Time Difference Between GMT and KST
Open the GMT to KST converter: Go to https://www.xconvert.com/time-converter/gmt-vs-kst to load a comparison grid with GMT and KST already shown as separate rows. This view is useful when you are scheduling a call between London-based teams using Greenwich Mean Time references and colleagues in South Korea, especially for logistics, gaming, manufacturing, or cross-border client support.
Add other relevant cities with the + Add City button: Click + Add City and search for cities such as London, Seoul, Singapore, or New York to compare GMT and KST against major business hubs. This is especially helpful for companies coordinating East Asia operations, Korean suppliers, or global teams where a Seoul office may need overlap with European headquarters and North American stakeholders.
Drag across the grid to select a meeting window: Click Select if needed, then drag across the GMT or KST row to highlight a time range in purple, such as 9:00 AM to 11:00 AM GMT. The tool will show that this corresponds to 6:00 PM to 8:00 PM KST on the same day, which is often workable for UK–Korea business calls, while 2:00 PM GMT becomes 11:00 PM KST, usually too late for routine team meetings.
Export the selected time for sharing: After selecting the range, 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 distributed team, because everyone can open the event in their own calendar and see the correct local time automatically without manually converting GMT to Korea Standard Time.
GMT vs KST Offset Explained
GMT is UTC+0 and KST is UTC+9, so KST is 9 hours ahead of GMT throughout the year. That means when it is 9:00 AM GMT, it is 6:00 PM KST, and when it is 12:00 noon GMT, it is 9:00 PM in South Korea. This large eastward offset matters for real working-hour overlap, because a standard 9 AM to 5 PM day in Korea corresponds to 12:00 AM to 8:00 AM GMT.
Korea Standard Time does not observe daylight saving time, so South Korea stays on UTC+9 all year. GMT itself is the fixed standard at UTC+0, with no daylight saving adjustment, so the pure GMT vs KST difference remains exactly 9 hours in every month. If you are comparing actual UK local time rather than GMT, the situation changes in summer because the UK switches to British Summer Time (BST, UTC+1), usually from the last Sunday in March to the last Sunday in October; during that period, Korea is 8 hours ahead of London local time, not 9.
This distinction is important for travel planning, trading desks, and remote operations. For example, a call planned for 8:00 AM GMT will be 5:00 PM KST, which can work well for same-day coordination between Europe and Seoul, but 4:00 PM GMT becomes 1:00 AM KST the next day, which is impractical for normal office hours. Teams in electronics, automotive supply chains, semiconductors, shipping, and online gaming often use this conversion because South Korea is a major hub for companies and partners connected to Seoul, Incheon, Busan, and surrounding industrial regions.
South Korea’s largest metro area, Seoul, has a population of roughly 9.3 million in the city and more than 25 million in the wider capital region, making KST highly relevant for international scheduling. In practical terms, the best overlap between GMT-based teams and KST-based teams is usually early morning in GMT and late afternoon to early evening in Korea. For example, 7:00 AM GMT = 4:00 PM KST, 8:00 AM GMT = 5:00 PM KST, and 9:00 AM GMT = 6:00 PM KST, which are common windows for UK–Korea status calls, supplier updates, and project handoffs.
Frequently Asked Questions
What is the exact time difference between GMT and KST?
KST is 9 hours ahead of GMT. If it is 10:00 AM GMT, it is 7:00 PM KST the same day; if it is 11:00 PM GMT, it is 8:00 AM KST the next day. Because both GMT and KST are fixed standards, this offset does not change seasonally.
Does the GMT to KST time difference ever change during the year?
The direct difference between GMT and KST does not change, because GMT stays at UTC+0 and KST stays at UTC+9 all year. However, people often mean UK local time when they say GMT, and the UK observes daylight saving time as BST (UTC+1) from the last Sunday in March to the last Sunday in October. During that summer period, South Korea is 8 hours ahead of London local time instead of 9.
Is South Korea on daylight saving time?
No, South Korea does not currently use daylight saving time. Korea Standard Time remains UTC+9 year-round, which makes scheduling more predictable for recurring meetings with Seoul, Busan, or Incheon. This consistency is useful for industries such as manufacturing, shipping, semiconductors, and customer support that rely on fixed international coordination windows.
What are the best meeting hours between GMT and KST?
The most practical overlap is usually 7:00 AM to 10:00 AM GMT, which corresponds to 4:00 PM to 7:00 PM KST. That range allows Europe-based teams to meet during the morning while Korean teams join in the late afternoon or early evening before the local workday ends. For example, 8:30 AM GMT = 5:30 PM KST, which is often a realistic slot for project reviews or supplier calls.
How do I convert GMT to KST quickly?
Add 9 hours to GMT to get KST. For example, 6:00 AM GMT = 3:00 PM KST, 1:00 PM GMT = 10:00 PM KST, and 8:00 PM GMT = 5:00 AM KST the next day. Using the visual grid on xconvert is faster for real scheduling because you can see whether a proposed slot lands in work hours, evening, or night for both sides.
Why is GMT vs KST important for business scheduling?
South Korea is a major economy with strong activity in electronics, semiconductors, automotive manufacturing, shipbuilding, e-commerce, and gaming, so international teams often need accurate GMT-to-KST conversion. A meeting that looks reasonable in Europe can easily fall after midnight in Korea if the 9-hour gap is overlooked. This is especially important for supplier negotiations, engineering handoffs, executive reviews, and support coverage planning.
When it is 9 AM GMT, what time is it in Korea?
When it is 9:00 AM GMT, it is 6:00 PM KST on the same calendar day. This is one of the most common reference points for UK–Korea coordination because it lands near the end of the Korean business day but still within a realistic meeting window. By contrast, 3:00 PM GMT is already 12:00 midnight KST, which is generally unsuitable for standard office meetings.