World Timezones

KST to IRST Converter

Compare IRST to KST instead
Korea Standard Time1:36 pmFri, Jun 5
Korea Standard TimeKST
Asia · UTC+9
1:36 pmFri, Jun 5
12a
1a
2a
3a
4a
5a
6a
7a
8a
9a
10a
11a
12p
1p
2p
3p
4p
5p
6p
7p
8p
9p
10p
11p
Iran Standard TimeIRST
Middle East · UTC+3:30
8:06 amFri, Jun 5
6p
7p
8p
9p
10p
11p
12a
1a
2a
3a
4a
5a
6a
7a
8a
9a
10a
11a
12p
1p
2p
3p
4p
5p

Offset

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

5.5 hours

Korea Standard Time (KST) is ahead of Iran Standard Time (IRST).

KST: UTC+9

IRST: UTC+3:30

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

When to schedule

Business-hours overlap: 3 PM–5 PM in Korea Standard Time (9 AM–11 AM in Iran Standard Time).

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

Suggested time: 4:00 PM Korea Standard Time (10:30 AM Iran 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

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

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

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

Quick reference

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

KSTIRSTDay
12:00 am6:30 pm-1 day
1:00 am7:30 pm-1 day
2:00 am8:30 pm-1 day
3:00 am9:30 pm-1 day
4:00 am10:30 pm-1 day
5:00 am11:30 pm-1 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
10:00 am4:30 amSame day
11:00 am5:30 amSame day
12:00 pm6:30 amSame day
1:00 pm7:30 amSame day
2:00 pm8:30 amSame day
3:00 pm9:30 amSame day
4:00 pm10:30 amSame day
5:00 pm11:30 amSame day
6:00 pm12:30 pmSame day
7:00 pm1:30 pmSame day
8:00 pm2:30 pmSame day
9:00 pm3:30 pmSame day
10:00 pm4:30 pmSame day
11:00 pm5:30 pmSame day

Daylight saving time

Neither Korea Standard Time nor Iran 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

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

Daylight overlap: 9h 31m — 10:20 AM–7:51 PM in Korea Standard Time (4:50 AM–2:21 PM in Iran 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 Korea Standard Time

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

Airports in Iran Standard Time

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

Related conversions

Common conversions

What is 9:00 am KST in IRST?
9:00 am KST is 3:30 am IRST.
What is 12:00 pm KST in IRST?
12:00 pm KST is 6:30 am IRST.
What is 12:30 pm KST in IRST?
12:30 pm KST is 7:00 am IRST.
What is 2:00 pm KST in IRST?
2:00 pm KST is 8:30 am IRST.
What is 5:00 pm KST in IRST?
5:00 pm KST is 11:30 am IRST.
What is 11:30 pm KST in IRST?
11:30 pm KST is 6:00 pm IRST.