GMT to EST converter
Eastern Time is 5 hours behind GMT in winter (EST, UTC−5) and 4 hours behind in summer (EDT, UTC−4). To convert GMT to EST, subtract 5 hours during standard time and 4 hours during daylight saving time. Only Eastern Time moves its clocks, so nothing else changes the gap.
GMT runs at UTC+0, Eastern Time at UTC−5 / UTC−4.
GMT to EST 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.
| GMT (GMT) | EST (Nov–Mar) | EDT (Mar–Nov) |
|---|---|---|
| 00:00 12:00 AM | 19:00 7:00 PM previous day | 20:00 8:00 PM previous day |
| 01:00 1:00 AM | 20:00 8:00 PM previous day | 21:00 9:00 PM previous day |
| 02:00 2:00 AM | 21:00 9:00 PM previous day | 22:00 10:00 PM previous day |
| 03:00 3:00 AM | 22:00 10:00 PM previous day | 23:00 11:00 PM previous day |
| 04:00 4:00 AM | 23:00 11:00 PM previous day | 00:00 12:00 AM |
| 05:00 5:00 AM | 00:00 12:00 AM | 01:00 1:00 AM |
| 06:00 6:00 AM | 01:00 1:00 AM | 02:00 2:00 AM |
| 07:00 7:00 AM | 02:00 2:00 AM | 03:00 3:00 AM |
| 08:00 8:00 AM | 03:00 3:00 AM | 04:00 4:00 AM |
| 09:00 9:00 AM | 04:00 4:00 AM | 05:00 5:00 AM |
| 10:00 10:00 AM | 05:00 5:00 AM | 06:00 6:00 AM |
| 11:00 11:00 AM | 06:00 6:00 AM | 07:00 7:00 AM |
| 12:00 12:00 PM | 07:00 7:00 AM | 08:00 8:00 AM |
| 13:00 1:00 PM | 08:00 8:00 AM | 09:00 9:00 AM |
| 14:00 2:00 PM | 09:00 9:00 AM | 10:00 10:00 AM |
| 15:00 3:00 PM | 10:00 10:00 AM | 11:00 11:00 AM |
| 16:00 4:00 PM | 11:00 11:00 AM | 12:00 12:00 PM |
| 17:00 5:00 PM | 12:00 12:00 PM | 13:00 1:00 PM |
| 18:00 6:00 PM | 13:00 1:00 PM | 14:00 2:00 PM |
| 19:00 7:00 PM | 14:00 2:00 PM | 15:00 3:00 PM |
| 20:00 8:00 PM | 15:00 3:00 PM | 16:00 4:00 PM |
| 21:00 9:00 PM | 16:00 4:00 PM | 17:00 5:00 PM |
| 22:00 10:00 PM | 17:00 5:00 PM | 18:00 6:00 PM |
| 23:00 11:00 PM | 18:00 6:00 PM | 19:00 7:00 PM |
How the GMT to EST conversion works
Converting GMT to EST means taking a wall-clock time in GMT (GMT, UTC+0) and expressing the same instant in Eastern Time (EST / EDT, UTC−5 / UTC−4). The arithmetic is one step: subtract 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 Etc/GMT and America/New_York, never with the abbreviations. On the target 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? UTC to EST reports the same numbers under that name.
Best time for meetings between GMT and EST
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.
EST (Nov–Mar)
A 9-to-6 working day in both zones overlaps for 4 hours: 2:00 PM–6:00 PM GMT is 9:00 AM–1:00 PM EST. Book inside that window and neither side is working outside normal hours.
EDT (Mar–Nov)
A 9-to-6 working day in both zones overlaps for 5 hours: 1:00 PM–6:00 PM GMT is 9:00 AM–2:00 PM EDT. 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).
Eastern Time is 5 hours behind GMT through the Nov–Mar window, and 4 hours behind through the Mar–Nov window.
US daylight saving time runs from the second Sunday in March to the first Sunday in November.
- GMT
- Etc/GMT
- GMT — UTC+0
- Eastern Time
- America/New_York
- EST / EDT — UTC−5 / UTC−4
Frequently asked questions
What is the time difference between GMT and EST?
Eastern Time runs 5 hours behind GMT during standard time and 4 hours behind during daylight saving time. In offset terms, GMT sits at UTC+0 and Eastern Time at UTC−5 / UTC−4. So 9:00 AM GMT is 4:00 AM EST, and 5:00 AM EDT once the clocks change. 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 GMT to EST 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 GMT in EST?
9:00 AM GMT is 4:00 AM in Eastern Time during standard time (EST) and 5:00 AM during daylight saving time (EDT). The rule is the same one the whole page runs on: subtract 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 GMT and EST stand for?
GMT stands for Greenwich Mean Time. EST stands for Eastern Standard Time, and EDT is Eastern Daylight Time. Both are display labels rather than rules: the offsets behind them come from the IANA identifiers Etc/GMT and America/New_York. GMT is fixed at UTC+0 as a time standard, but people often write it when they mean UK local time, which becomes BST in summer.
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.