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EST to IST converter

India Standard Time is 10 hours 30 minutes ahead of Eastern Time while Eastern Time is on EST (UTC−5), and 9 hours 30 minutes ahead while Eastern Time is on EDT (UTC−4). To convert EST to IST, add 10 hours 30 minutes in winter and 9 hours 30 minutes in summer.

Eastern Time EST
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India Standard Time IST
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Eastern Time runs at UTC−5 / UTC−4, India Standard Time at UTC+5:30.

EST to IST conversion table

Every hour of the day converted for both halves of the year. The two columns differ because Eastern Time changes its offset for daylight saving time.

Hour-by-hour conversion from Eastern Time to India Standard Time
Eastern Time (EST / EDT) IST (EST, Nov–Mar) IST (EDT, Mar–Nov)
00:00 12:00 AM 10:30 10:30 AM 09:30 9:30 AM
01:00 1:00 AM 11:30 11:30 AM 10:30 10:30 AM
02:00 2:00 AM 12:30 12:30 PM 11:30 11:30 AM
03:00 3:00 AM 13:30 1:30 PM 12:30 12:30 PM
04:00 4:00 AM 14:30 2:30 PM 13:30 1:30 PM
05:00 5:00 AM 15:30 3:30 PM 14:30 2:30 PM
06:00 6:00 AM 16:30 4:30 PM 15:30 3:30 PM
07:00 7:00 AM 17:30 5:30 PM 16:30 4:30 PM
08:00 8:00 AM 18:30 6:30 PM 17:30 5:30 PM
09:00 9:00 AM 19:30 7:30 PM 18:30 6:30 PM
10:00 10:00 AM 20:30 8:30 PM 19:30 7:30 PM
11:00 11:00 AM 21:30 9:30 PM 20:30 8:30 PM
12:00 12:00 PM 22:30 10:30 PM 21:30 9:30 PM
13:00 1:00 PM 23:30 11:30 PM 22:30 10:30 PM
14:00 2:00 PM 00:30 12:30 AM next day 23:30 11:30 PM
15:00 3:00 PM 01:30 1:30 AM next day 00:30 12:30 AM next day
16:00 4:00 PM 02:30 2:30 AM next day 01:30 1:30 AM next day
17:00 5:00 PM 03:30 3:30 AM next day 02:30 2:30 AM next day
18:00 6:00 PM 04:30 4:30 AM next day 03:30 3:30 AM next day
19:00 7:00 PM 05:30 5:30 AM next day 04:30 4:30 AM next day
20:00 8:00 PM 06:30 6:30 AM next day 05:30 5:30 AM next day
21:00 9:00 PM 07:30 7:30 AM next day 06:30 6:30 AM next day
22:00 10:00 PM 08:30 8:30 AM next day 07:30 7:30 AM next day
23:00 11:00 PM 09:30 9:30 AM next day 08:30 8:30 AM next day

How the EST to IST conversion works

Converting EST to IST means taking a wall-clock time in Eastern Time (EST / EDT, UTC−5 / UTC−4) and expressing the same instant in India Standard Time (IST, UTC+5:30). The arithmetic is one step: add 10 hours 30 minutes while Eastern Time is on standard time, and 9 hours 30 minutes while it is on daylight saving time. Applying the gap pushes part of the day onto a different calendar date — the table below marks every row that shifts. In code, store the instant in UTC and convert with the IANA identifiers America/New_York and Asia/Kolkata, never with the abbreviations. One note on the source label: EST is also used for Australian Eastern Standard Time (UTC+10), so the abbreviation alone is ambiguous. On the target label: IST is also used for Irish Standard Time and Israel Standard Time, so the abbreviation alone is ambiguous.

Best time for meetings between EST and IST

Working hours are taken as 09:00–18:00 in each zone. The window in force depends on the date, so both halves of the year are listed where they differ.

IST (EST, Nov–Mar)

 

A 9-to-6 working day in the two zones does not overlap at all. The IST working day runs from 10:30 PM the previous day to 7:30 AM in EST terms, so a shared call means an early start on one side or a late finish on the other.

IST (EDT, Mar–Nov)

 

A 9-to-6 working day in the two zones does not overlap at all. The IST working day runs from 11:30 PM the previous day to 8:30 AM in EDT terms, so a shared call still costs one side an early morning or a late evening.

Daylight saving time: which side moves

Only Eastern Time shifts. India Standard Time holds a single offset all year, so every change in the gap comes from Eastern Time moving between EST (UTC−5) and EDT (UTC−4).

India Standard Time is 10 hours 30 minutes ahead of Eastern Time through the Nov–Mar window, and 9 hours 30 minutes ahead through the Mar–Nov window.

US daylight saving time runs from the second Sunday in March to the first Sunday in November.

Eastern Time
America/New_York
EST / EDT — UTC−5 / UTC−4
India Standard Time
Asia/Kolkata
IST — UTC+5:30

Frequently asked questions

What is the time difference between EST and IST?

India Standard Time runs 10 hours 30 minutes ahead of Eastern Time during standard time and 9 hours 30 minutes ahead during daylight saving time. In offset terms, Eastern Time sits at UTC−5 / UTC−4 and India Standard Time at UTC+5:30. So 9:00 AM EST is 7:30 PM IST, while 9:00 AM EDT is 6:30 PM IST.

Does the EST to IST difference change with daylight saving time?

The difference does change. Eastern Time moves its clocks, so the gap swings between 10 hours 30 minutes and 9 hours 30 minutes depending on the date. In the US that means clocks move forward on the second Sunday of March and back on the first Sunday of November. Convert against the IANA rules for the exact date rather than a remembered offset.

What time is 9 am EST in IST?

9:00 AM EST is 7:30 PM IST. The same clock reading in summer is EDT, and 9:00 AM EDT is 6:30 PM IST. The rule is the same one the whole page runs on: add 10 hours 30 minutes in winter and 9 hours 30 minutes in summer. Check the hour-by-hour table for any other starting hour, including the rows that land on the previous or next calendar day.

What do EST and IST stand for?

EST stands for Eastern Standard Time, and EDT is Eastern Daylight Time. IST stands for India Standard Time. Both are display labels rather than rules: the offsets behind them come from the IANA identifiers America/New_York and Asia/Kolkata. EST is also used for Australian Eastern Standard Time (UTC+10), so the abbreviation alone is ambiguous.

Related conversions

Need more than two zones at once? The full timezone converter shows a single moment across up to six IANA timezones, for any date you choose.

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