India Standard Time (ist) is used in India. The IANA timezone identifier is Asia/Kolkata.

Korea Standard Time (kst) is used in South Korea. The IANA timezone identifier is Asia/Seoul.

IST to KST Time Converter

India Standard Time → Korea Standard Time

IST = UTC+5:30KST = UTC+9

⚠️ IST is ambiguous — on this page it means India Standard Time. It also refers to:

Ireland Standard Time (Dublin) → KST ↗Israel Standard Time (Jerusalem) → KST ↗

ClockinSync

BASE

09:00

Work Clients Team +

00:0006:0012:0018:0024:00

KST (Seoul)

South Korea · +3.5h

12:30

London

United Kingdom · -4.5h

04:30

New York

USA · -9.5h

23:30-1 day

Tokyo

Japan · +3.5h

12:30

Dubai

United Arab Emirates · -1.5h

07:30

How far apart are IST (Mumbai) and KST (Seoul)?

IST (Mumbai) is 4 hours 30 minutes behind KST (Seoul). When IST (Mumbai) clocks hit noon, KST (Seoul) reads 15:00.

IST (Mumbai) is in the Asia/Kolkata timezone. KST (Seoul) is in Asia/Seoul. The difference is 3.5 hours 30 minutes.

Daily overlap window

Every working day, IST (Mumbai) and KST (Seoul) are both in business hours for 4.5 hours simultaneously.

00:0006:0012:0018:0024:00

IST (Mumbai)

KST (Seoul)

Overlap (4.5h)

When to schedule across time zones

Both IST (Mumbai) and KST (Seoul) are in standard hours simultaneously for 4.5h per day. 3 recommended slots shown below.

09:00 Mumbai / 12:00 Seoul✓ Both working

10:00 Mumbai / 13:00 Seoul✓ Both working

11:00 Mumbai / 14:00 Seoul✓ Both working

Based on standard 09:00–17:00 working hours in each location's local time.

Holiday calendar for both locations

IST (Mumbai)

No upcoming public holidays this year.

KST (Seoul)7 holidays

Aug 15Liberation Day

Sep 24Chuseok

Sep 25Chuseok

Sep 26Chuseok

Oct 3National Foundation Day

Working across IST (Mumbai) and KST (Seoul)

Working across IST (Mumbai) (India) and KST (Seoul) (South Korea) involves a 3.5-hour gap. The good news: there is a 4.5-hour mutual window in standard business hours that lets both sides collaborate without anyone joining at an unreasonable hour.

💡 Best practice for cross-timezone meetings

✅

09:00–10:00 in IST (Mumbai) = 12:00–13:00 in KST (Seoul). Both sides are in standard business hours during this window.

✅

10:00–11:00 in IST (Mumbai) = 13:00–14:00 in KST (Seoul). Both sides are in standard business hours during this window.

✅

11:00–12:00 in IST (Mumbai) = 14:00–15:00 in KST (Seoul). Both sides are in standard business hours during this window.

DST transitions can silently shift your meeting times by an hour. The ClockinSync Chrome Extension tracks these changes automatically so you never get caught off guard.

Get the Extension — Free →

Use the time slider above to find the exact equivalent time for any moment in IST (Mumbai). The input bar accepts natural language like "3pm", "15:30", or "9am Rome" for instant conversions.

IST (Mumbai) ↔ KST (Seoul)

5h of business hours overlap daily (09:00–17:00)

IST (Mumbai)

KST (Seoul)

00:00

03:30

01:00

04:30

02:00

05:30

03:00

06:30

04:00

07:30

05:00

08:30

06:00

09:30Working

07:00

10:30Working

08:00

11:30Working

09:00Working

12:30Working

10:00Working

13:30Working

11:00Working

14:30Working

12:00Working

15:30Working

13:00Working

16:30Working

14:00Working

17:30off

15:00Working

18:30off

16:00Working

19:30off

17:00

20:30

18:00

21:30

19:00

22:30

20:00

23:30

21:00

00:30+1d

22:00

01:30+1d

23:00

02:30+1d

Working hours: 09:00–17:00 local. Green = both working. Purple = one side only.

Frequently Asked Questions

What is the difference between ist and kst?

India Standard Time (ist) is UTC+5:30 and Korea Standard Time (kst) is UTC+9. The difference between them is 3.5 hours.

Where is ist used?

India Standard Time (ist) is used in India and surrounding regions. The IANA timezone identifier is Asia/Kolkata. Note: ist is ambiguous and may refer to other timezones.

Where is kst used?

Korea Standard Time (kst) is used in South Korea and surrounding regions. The IANA timezone identifier is Asia/Seoul.

How do I convert ist to kst?

Use the interactive converter above. Drag the time slider to any ist time and the kst equivalent updates instantly. You can also type a time like "3pm" or "15:00" in the input bar.

Popular IST conversions

IST → London IST → New York IST → Tokyo IST → Dubai IST → Sydney IST → Paris IST → Berlin IST → Singapore IST → Los Angeles IST → Toronto

Popular KST conversions

London → KST New York → KST Tokyo → KST Dubai → KST Sydney → KST Paris → KST Berlin → KST Singapore → KST Los Angeles → KST Toronto → KST