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EST to GMT converter

GMT is 5 hours ahead of Eastern Time while Eastern Time is on EST (UTC−5), and 4 hours ahead while Eastern Time is on EDT (UTC−4). To convert EST to GMT, add 5 hours in winter and 4 hours in summer.

Eastern Time EST
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GMT GMT
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Eastern Time runs at UTC−5 / UTC−4, GMT at UTC+0.

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

How the EST to GMT conversion works

Converting EST to GMT means taking a wall-clock time in Eastern Time (EST / EDT, UTC−5 / UTC−4) and expressing the same instant in GMT (GMT, UTC+0). The arithmetic is one step: add 5 hours while Eastern Time is on standard time, and 4 hours 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 Etc/GMT, 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. IANA identifiers carry the full offset history of a region, including every daylight saving transition ever legislated, which is why databases, schedulers, and APIs should store them.

GMT vs UTC

GMT on this page names the fixed Etc/GMT zone, which is identical to UTC+0 every day of the year — the table above is exact regardless of which term you use. It is not the same thing as UK local time: the United Kingdom itself keeps GMT only from late October to late March and observes British Summer Time (UTC+1) the rest of the year, one hour ahead of every GMT value on this page. If your search for GMT meant the UK's current clock rather than the fixed reference offset, check which side of that switch today falls on.

Meant the fixed reference rather than UK local time? EST to UTC reports the same numbers under that name.

Best time for meetings between EST and GMT

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.

GMT (EST, Nov–Mar)

 

A 9-to-6 working day in both zones overlaps for 4 hours: 9:00 AM–1:00 PM EST is 2:00 PM–6:00 PM GMT. Book inside that window and neither side is working outside normal hours.

GMT (EDT, Mar–Nov)

 

A 9-to-6 working day in both zones overlaps for 5 hours: 9:00 AM–2:00 PM EDT is 1:00 PM–6:00 PM GMT. A call booked inside that window keeps both sides within a normal working day.

Daylight saving time: which side moves

Only Eastern Time shifts. GMT 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).

GMT is 5 hours ahead of Eastern Time through the Nov–Mar window, and 4 hours 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
GMT
Etc/GMT
GMT — UTC+0

Frequently asked questions

What is the time difference between EST and GMT?

GMT runs 5 hours ahead of Eastern Time during standard time and 4 hours ahead during daylight saving time. In offset terms, Eastern Time sits at UTC−5 / UTC−4 and GMT at UTC+0. So 9:00 AM EST is 2:00 PM GMT, while 9:00 AM EDT is 1:00 PM GMT. The hour-by-hour table on this page lists the conversion for all 24 hours so you do not have to do the arithmetic.

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

The difference does change. Eastern Time moves its clocks, so the gap swings between 5 hours and 4 hours 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. GMT here is the fixed UTC+0 standard; the United Kingdom itself leaves GMT for BST (UTC+1) each summer.

What time is 9 am EST in GMT?

9:00 AM EST is 2:00 PM GMT. The same clock reading in summer is EDT, and 9:00 AM EDT is 1:00 PM GMT. The rule is the same one the whole page runs on: add 5 hours in winter and 4 hours 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 GMT stand for?

EST stands for Eastern Standard Time, and EDT is Eastern Daylight Time. GMT stands for Greenwich Mean Time. Both are display labels rather than rules: the offsets behind them come from the IANA identifiers America/New_York and Etc/GMT. 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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