KST to EST Converter (Korea Time to Eastern Time)

Mid-January 2026: EST is 14 hours behind KST. Mid-July 2026: EDT is 13 hours behind KST.

This page answers the question from the Korean side: what is the clock reading in New York, Boston, Washington or Atlanta when it is a given time in Seoul? Korea Standard Time never changes, so the answer depends only on whether the United States is on standard time or daylight saving time on that date.

Because Seoul is a calendar day ahead for most of the day, the New York answer is usually the previous date. Nine o'clock on a Tuesday morning in Seoul is a Monday evening in the Eastern zone, and the converter shows the date as well as the hour.

How to use this tool

1. Pick a date and time in KST. The date matters when daylight saving time is in force.
2. Read the matching time in EST, with both UTC offsets.
3. Use "Use current time" for now, or the tables below for a quick look.

Formula

EST time = KST time − (KST UTC offset) + (EST UTC offset)

The converter looks up both UTC offsets for the actual instant in the saved IANA time zone rules, so daylight saving changes are included automatically.

Example

Worked with the saved rules:

9:00 AM KST on March 2, 2026 = 7:00 PM EST (previous day)

6:30 PM KST on August 3, 2026 = 5:30 AM EDT

Time difference through the year

The difference depends on the date when either place moves its clocks. These are the offsets on two reference days, from the saved IANA rules:

Clock changes in 2026

Between these dates the difference shifts by the size of the change.

KST to EST time table

Each hour in Korea Standard Time with the matching Eastern Time time in winter and summer (reference days in January and July).

EST to KST time table

Each hour in Eastern Time with the matching Korea Standard Time time in winter and summer (reference days in January and July).

Hours that work in both places

Hours (on the January reference day) that fall between 8:00 AM and 8:00 PM in both KST and EST:

Check the summer column above when one of the places is on daylight saving time.

Following the US stock market from Korea

The New York Stock Exchange opens its regular session at 9:30 a.m. Eastern. For an investor in Korea that is 11:30 p.m. in winter and 10:30 p.m. while the United States is on daylight saving time, and the 4:00 p.m. closing bell falls at 6:00 a.m. or 5:00 a.m. the next morning.

The one-hour shift is easy to miss. Korea does not change its clocks, so every spring and autumn the US session moves by an hour on a Korean clock. The exchange publishes its holidays and early-close days, which are quoted in Eastern Time.

Calling family and colleagues in the United States

The friendliest time to call a US contact from Korea is your morning, when it is the previous evening in the Eastern zone. A call at 9 a.m. in Seoul reaches New York at 7 p.m. in winter and 8 p.m. in summer, before most people have gone to bed.

A call placed in the Korean evening works poorly: 9 p.m. in Seoul is 7 a.m. in New York in winter, which is early for many households, and the pattern is the same for students living in the Boston area or the Washington region.