9am in Seongnam-si is 8pm in Eastern Standard Time on the previous day.

Frequently asked

Quick answers about converting between Seongnam-si and Eastern Standard Time. Can't find what you need? Email [email protected].

What is the time difference between Seongnam-si and Eastern Standard Time?

Seongnam-si is 13 hours ahead of Eastern Standard Time right now. We always show the live, daylight-saving-correct difference, so this figure already accounts for whichever side is observing summer time today.

When it's 9am in Seongnam-si, what time is it in Eastern Standard Time?

9am in Seongnam-si is 8pm in Eastern Standard Time on the previous day. That's already evening in Eastern Standard Time, after the typical working day ends. Use the hour-by-hour table above to read any other time across.

What's the best time for a call between Seongnam-si and Eastern Standard Time?

There's no comfortable 9-to-5 overlap between Seongnam-si and Eastern Standard Time — they sit on opposite sides of the planet's working day. Plan for an early or late call on one side, or hand work off asynchronously.

Does this account for daylight saving time?

Yes. We track every clock change in both places, so the abbreviations you see — KST and EDT — are the ones actually in effect right now, not a fixed all-year value. When either side changes its clocks, this page updates automatically.

Why is the date sometimes different on each side?

When two places are far enough apart, the same moment can fall on different calendar days. That is why some conversions are marked "previous day" or "next day" — it is the same instant in time, read off two clocks that crossed midnight at different points.