World Timezones

IRST to KST Converter

Compare KST to IRST instead
Iran Standard Time8:06 amFri, Jun 5
Iran Standard TimeIRST
Middle East · UTC+3:30
8:06 amFri, Jun 5
12a
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12p
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11p
Korea Standard TimeKST
Asia · UTC+9
1:36 pmFri, Jun 5
5a
6a
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8a
9a
10a
11a
12p
1p
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12a
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Offset

The time difference between Iran Standard Time and Korea Standard Time is 5.5 hours.

5.5 hours

Iran Standard Time (IRST) is behind Korea Standard Time (KST).

IRST: UTC+3:30

KST: UTC+9

Neither Iran Standard Time nor Korea Standard Time is currently observing daylight saving time.

When to schedule

Business-hours overlap: 9 AM–12 PM in Iran Standard Time (2 PM–5 PM in Korea Standard Time).

Both teams are in working hours during this window on weekdays.

Suggested time: 10:00 AM Iran Standard Time (3:30 PM Korea Standard Time).

Public holidays in 2026

National public holidays can affect availability — a counterpart is likely off work on their own holidays, so it's worth planning meetings and deadlines around them.

South Korea

  • New Year's DayThu, Jan 1
  • Lunar New YearMon, Feb 16
  • Lunar New YearTue, Feb 17
  • Lunar New YearWed, Feb 18
  • Independence Movement DayMon, Mar 2
  • Labour DayFri, May 1
  • Children's DayTue, May 5
  • Buddha's BirthdayMon, May 25
  • Local Election DayWed, Jun 3
  • Memorial DaySat, Jun 6
  • Constitution DayFri, Jul 17
  • Liberation DayMon, Aug 17
  • ChuseokThu, Sep 24
  • ChuseokFri, Sep 25
  • ChuseokSat, Sep 26
  • National Foundation DayMon, Oct 5
  • Hangul DayFri, Oct 9
  • Christmas DayFri, Dec 25

About these zones

Iran Standard Time is also known as IRST. To call Iran, dial +98.

Korea Standard Time is also known as KST. To call South Korea, dial +82.

Korea Standard Time is approximately 4,050 miles northeast of Iran Standard Time.

Quick reference

Full 24-hour conversion table — tap any time to open it in the converter.

IRSTKSTDay
12:00 am5:30 amSame day
1:00 am6:30 amSame day
2:00 am7:30 amSame day
3:00 am8:30 amSame day
4:00 am9:30 amSame day
5:00 am10:30 amSame day
6:00 am11:30 amSame day
7:00 am12:30 pmSame day
8:00 am1:30 pmSame day
9:00 am2:30 pmSame day
10:00 am3:30 pmSame day
11:00 am4:30 pmSame day
12:00 pm5:30 pmSame day
1:00 pm6:30 pmSame day
2:00 pm7:30 pmSame day
3:00 pm8:30 pmSame day
4:00 pm9:30 pmSame day
5:00 pm10:30 pmSame day
6:00 pm11:30 pmSame day
7:00 pm12:30 am+1 day
8:00 pm1:30 am+1 day
9:00 pm2:30 am+1 day
10:00 pm3:30 am+1 day
11:00 pm4:30 am+1 day

Daylight saving time

Neither Iran Standard Time nor Korea Standard Time observes daylight saving time. The offset between these zones remains constant year-round.

See the daylight saving time page for transition dates across every time zone.

Daylight today

Iran Standard Time
Sunrise
4:50 AM
Sunset
7:18 PM
Day length
14h 28m
Korea Standard Time
Sunrise
5:12 AM
Sunset
7:51 PM
Day length
14h 38m

Daylight overlap: 9h 31m — 4:50 AM–2:21 PM in Iran Standard Time (10:20 AM–7:51 PM in Korea Standard Time). Both locations are in daylight during this window.

Cities in these zones

Cities in Iran Standard Time

Browse all cities to see the current local time anywhere.

Airports in these zones

Airports in Iran Standard Time

  • IKA
  • THR
  • MHD
  • IFN
  • PYK
  • TBZ

Airports in Korea Standard Time

  • GMP
  • ICN
  • PUS
  • TAE
  • CJJ
  • KWJ
  • MWX

Related conversions

Common conversions

What is 9:00 am IRST in KST?
9:00 am IRST is 2:30 pm KST.
What is 12:00 pm IRST in KST?
12:00 pm IRST is 5:30 pm KST.
What is 12:30 pm IRST in KST?
12:30 pm IRST is 6:00 pm KST.
What is 2:00 pm IRST in KST?
2:00 pm IRST is 7:30 pm KST.
What is 5:00 pm IRST in KST?
5:00 pm IRST is 10:30 pm KST.
What is 11:30 pm IRST in KST?
11:30 pm IRST is 5:00 am KST, the next day.