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South Korea to Iran

-5h 30m

South Korea

KSTSOURCE
UTC+09:00
HH12
:
MM00
  
12:00 (24-hr)
12 AM6 AM12 PM6 PM12 AM

Iran

IRST
UTC+03:30
HH06
:
MM30
  
06:30 (24-hr)
12 AM6 AM12 PM6 PM12 AM
South Korea
Iran
12:00 AM
6:30 PM-1
2:00 AM
8:30 PM-1
4:00 AM
10:30 PM-1
6:00 AM
12:30 AM
8:00 AM
2:30 AM
10:00 AM
4:30 AM
12:00 PM
6:30 AM
2:00 PM
8:30 AM
4:00 PM
10:30 AM
6:00 PM
12:30 PM
8:00 PM
2:30 PM
10:00 PM
4:30 PM

Green rows indicate typical business hours (9 AM - 5 PM)

KST and IRST on the World Map

The map below highlights the KST (Korea Standard Time) and IRST (Iran Standard Time) timezone regions across the globe.

KSTIRSTSeoulBusanIncheonDaeguTehranIsfahanMashhadTabriz
KST Zone
→
IRST Zone

Explore all world timezones interactively →

KST – Korea Standard Time

UTC+09:00

Korea Standard Time (KST) is the time zone for South Korea, 9 hours ahead of UTC.

Countries in KST
South KoreaNorth Korea
Major Cities in KST
SeoulBusanIncheonDaeguDaejeonPyongyang
Key Facts about KST
  • •South Korea does not observe daylight saving time.
  • •Seoul is home to Samsung, LG, and Hyundai headquarters.
  • •KST is the same offset as JST (UTC+09:00).
Daylight Saving:No – UTC+09:00 year-round
Learn more about KST on Wikipedia

IRST – Iran Standard Time

UTC+03:30

Iran Standard Time (IRST) is the time zone for Iran, 3 hours and 30 minutes ahead of UTC.

Countries in IRST
Iran
Major Cities in IRST
TehranIsfahanMashhadTabrizShirazKaraj
Key Facts about IRST
  • •IRST is one of only a few time zones with a 30-minute offset.
  • •Iran observes daylight saving time, switching to IRDT (UTC+04:30).
  • •Tehran has a metropolitan population of over 16 million.
Daylight Saving:Yes – switches to IRDT
Learn more about IRST on Wikipedia

Time Conversion Guide: South Korea to Iran

South Korea runs on Korean Standard Time (KST) at UTC+09:00. Iran runs on Iran Standard Time (IRST) at UTC+03:30. That puts South Korea 5 hours 30 minutes behind Iran — a difference of -5h 30m at the current offsets.

In practice, when it is 9:00 AM in South Korea it is 3:30 AM in Iran. Midnight in South Korea is 6:30 PM in Iran. Neither zone observes daylight saving time, so the offset between them stays constant all year.

South Korea to Iran time conversion table

South Korea (KST)Iran (IRST)Day
12:00 AM6:30 PMprevious day
6:00 AM12:30 AMsame day
7:00 AM1:30 AMsame day
8:00 AM2:30 AMsame day
9:00 AM3:30 AMsame day
12:00 PM6:30 AMsame day
3:00 PM9:30 AMsame day
5:00 PM11:30 AMsame day
6:00 PM12:30 PMsame day
9:00 PM3:30 PMsame day

Why people convert South Korea to Iran time

  • Scheduling a call from South Korea to Iran: a 10:00 AM start in South Korea lands at 4:30 AM in Iran, so you can confirm the slot without doing the arithmetic yourself.
  • Finding shared working hours: both South Korea and Iran are inside the 9-to-5 working day between 2:30 PM and 5:00 PM KST time (9:00 AM–11:30 AM IRST). That is roughly 2 hours 30 minutes of usable overlap.
  • Watching a live event or market open: South Korea viewers need 3:30 AM in Iran to catch a 9:00 AM start there, and 5:30 AM if the event is anchored to South Korea.
  • Always state the zone abbreviation, not just the hour. "3:00 PM KST" is unambiguous; "3 PM" across a -5h 30m gap is not.
  • Block 2:30 PM–5:00 PM KST as the recurring meeting window if you work primarily from South Korea and need Iran colleagues present.

About KST (Korea Standard Time)

Korea Standard Time (KST) is the time zone used in South Korea. It shares the same UTC offset as Japan Standard Time but is a distinct time zone. South Korea does not observe daylight saving time. Seoul, the capital, is a major global tech and business hub.

About IRST (Iran Standard Time)

Iran Standard Time (IRST) is one of the few time zones with a 30-minute offset. Iran observes daylight saving time (IRDT, UTC+04:30) from late March to late September. Tehran, the capital, is one of the largest cities in the Middle East.

Best time to call between South Korea and Iran

Both South Korea and Iran sit inside the 9 AM – 5 PM working day between 2:30 PM–5:00 PM KST, which is 9:00 AM–11:30 AM IRST. That gives roughly 2 hours and 30 minutes of shared time — the safest window for a live call or meeting.

Business hours overlap

South Korea and Iran overlap for about 2 hours during the working day — enough for meetings if you avoid the edges of the window.

South Korea is 5 hours 30 minutes behind Iran (KST UTC+09:00 → IRST UTC+03:30). The shared working window is 2:30 PM–5:00 PM KST. Remember to re-check around daylight-saving transitions.

Frequently Asked Questions

What is the time difference between South Korea and Iran?

South Korea (KST, UTC+09:00) is 5 hours 30 minutes behind Iran (IRST, UTC+03:30). The gap is currently -5h 30m.

How do I convert South Korea time to Iran time?

Add -5h 30m to South Korea local time. For example, 9:00 AM in South Korea is 3:30 AM in Iran.

What time is it in Iran right now?

Iran uses IRST at UTC+03:30. Use the live converter at the top of this page — it updates in real time and already accounts for the -5h 30m offset from South Korea.

What is the best time to call Iran from South Korea?

Call between 2:30 PM and 5:00 PM KST — that maps to 9:00 AM–11:30 AM IRST and keeps both parties inside the working day.

Which is behind, South Korea or Iran?

South Korea is 5 hours 30 minutes behind Iran. When it is 12:00 PM in South Korea it is 6:30 AM in Iran.

Do South Korea and Iran use different time zones?

South Korea (South Korea) uses KST at UTC+09:00, while Iran (Iran) uses IRST at UTC+03:30. The IANA identifiers are Asia/Seoul and Asia/Tehran.

Does daylight saving time affect the South Korea–Iran difference?

Neither zone observes daylight saving time, so the -5h 30m offset between South Korea and Iran is fixed all year.

Which other cities share South Korea's time zone?

KST also covers Seoul, Busan, Incheon, Daegu, Daejeon, Pyongyang.

Which countries use KST, South Korea's zone?

KST is used in South Korea, North Korea.

Is there a day difference between South Korea and Iran?

Not normally. The -5h 30m gap only pushes the date over the previous day.

What is the time difference between South Korea and Iran?

Iran is -5h 30m from South Korea.

What timezone is South Korea in?

South Korea operates on its local timezone.

What timezone is Iran in?

Iran operates on its local timezone.

Which countries use KST (Korea Standard Time)?

KST is used in South Korea, North Korea.

Does KST observe daylight saving time?

No, KST does not observe daylight saving time and remains at UTC+09:00 year-round.

What are some interesting facts about KST?

South Korea does not observe daylight saving time. Seoul is home to Samsung, LG, and Hyundai headquarters.

Which cities are in the IRST timezone?

Major cities in the IRST timezone include Tehran, Isfahan, Mashhad, Tabriz, Shiraz, Karaj.

What is the UTC offset for IRST?

Iran Standard Time (IRST) is at UTC+03:30. During daylight saving time, it shifts to IRDT.

What should I know about the IRST timezone?

IRST is one of only a few time zones with a 30-minute offset. Iran observes daylight saving time, switching to IRDT (UTC+04:30).

When is it midnight in South Korea, what time is it in Iran?

When it is 12:00 AM (midnight) in South Korea (KST), it is -5h 30m later in Iran (IRST).