Converter · ET → UTC

EST to UTC: Eastern Time to Coordinated Universal Time

UTC is 5 hours ahead of EST and 4 hours ahead of EDT. Add 5 hours in winter (9:00 AM EST = 14:00 UTC) and 4 hours in summer (9:00 AM EDT = 13:00 UTC).

Now in Eastern Time
--:-- ET
Now in UTC
--:-- UTC
Eastern offset now
UTC−05:00
Difference
UTC is 5 hours ahead of ET
Next Eastern change
Second Sunday in March

How do you convert EST to UTC?

  1. Find the offset for the date. Eastern Time is on EST (UTC−5) from the first Sunday in November to the second Sunday in March and on EDT (UTC−4) the rest of the year. The live Eastern Time clock shows which one applies today.
  2. Add the hours: 5 for EST, 4 for EDT. An offset of −05:00 means local time is five hours behind UTC, so going to UTC you add.
  3. Roll the date if you pass midnight. From 7:00 PM EST, or 8:00 PM EDT, onward the UTC date is already tomorrow.

Going the other way, subtract: 00:00 UTC on January 1 is 7:00 PM EST on December 31. UTC is normally written on the 24-hour clock – 14:00 rather than 2:00 PM. The military time page explains that format and the zone letters, in which UTC is "Z" (Zulu), EST is "R" (Romeo) and EDT is "Q" (Quebec).

Why does the EST–UTC difference change when UTC never does?

UTC has no daylight saving time, no seasons and no location. It is not the time anywhere in particular; it is the reference from which every zone's offset is counted, as the UTC offset guide explains.

When the US springs forward, nothing happens to UTC. Eastern Time's offset moves from −5 to −4, so the difference shrinks from 5 hours to 4; in November it moves back. Both changes happen at fixed UTC instants – 07:00 UTC on the second Sunday in March and 06:00 UTC on the first Sunday in November, which in 2027 are March 14 and November 7.

That is why conversion to UTC is the first step of almost every time calculation. Two Eastern times six months apart cannot be compared without knowing their offsets; two UTC times can simply be subtracted.

During 2027 UTC stays fixed while Eastern Time steps from UTC−5 to UTC−4 on March 14 and back on November 7, so the difference is 5 hours, then 4, then 5 UTC ±0 – never changes +5 h+4 h+5 h EST · UTC−5EDT · UTC−4EST Mar 14, 07:00 UTCNov 7, 06:00 UTC JanMarMayJulSepNovDec
2027: UTC is flat; only Eastern Time moves.

EST to UTC conversion table

Each row is one hour on the Eastern clock. Use the EST column in winter and the EDT column in summer; in the evening rows the UTC date is already the next day.

UTC in 24-hour format. EST column: November to March; EDT column: March to November. Highlighted: the 9:00 AM–5:00 PM Eastern business day.
Eastern (ET)UTC when ET is on ESTUTC when ET is on EDT
12:00 AM05:0004:00
1:00 AM06:0005:00
2:00 AM07:0006:00
3:00 AM08:0007:00
4:00 AM09:0008:00
5:00 AM10:0009:00
6:00 AM11:0010:00
7:00 AM12:0011:00
8:00 AM13:0012:00
9:00 AM14:0013:00
10:00 AM15:0014:00
11:00 AM16:0015:00
12:00 PM17:0016:00
1:00 PM18:0017:00
2:00 PM19:0018:00
3:00 PM20:0019:00
4:00 PM21:0020:00
5:00 PM22:0021:00
6:00 PM23:0022:00
7:00 PM00:00 (next day)23:00
8:00 PM01:00 (next day)00:00 (next day)
9:00 PM02:00 (next day)01:00 (next day)
10:00 PM03:00 (next day)02:00 (next day)
11:00 PM04:00 (next day)03:00 (next day)

What does the "Z" in a timestamp mean?

ISO 8601, the international standard for writing dates and times, marks UTC with the letter Z for "zero offset", spoken "Zulu" from the NATO phonetic alphabet. Every other zone is written as a numeric offset. In winter, 2027-01-15T09:00:00-05:00 and 2027-01-15T14:00:00Z are the same instant; in summer, 2027-07-15T09:00:00-04:00 equals 2027-07-15T13:00:00Z. (Machine formats use a plain hyphen for the minus sign.)

For developers, three habits prevent most Eastern Time bugs:

  • Store and transmit UTC, or ISO 8601 with an explicit offset, and convert to local time only for display.
  • Name the zone America/New_York (or America/Toronto), never a fixed offset. The legacy IANA zone EST is a fixed UTC−5 with no daylight time, so software set to it is an hour off all summer.
  • Run interval jobs on UTC. On the spring-forward night Eastern clocks have no 2:30 AM, and in November 1:30 AM happens twice.

The glossary defines offset, IANA zone and the other terms used here.

Why is UTC kept by atomic clocks?

Since 1967 the second has been defined by atoms, not by the sky: 9,192,631,770 cycles of the radiation from a particular transition of the caesium-133 atom. The Earth is a much worse clock. Tides and movements inside the planet make the length of a day wander by milliseconds, so a time scale based on rotation (called UT1) drifts against an atomic one.

The International Bureau of Weights and Measures (BIPM) near Paris combines hundreds of atomic clocks in national laboratories into International Atomic Time (TAI), a continuous count of seconds. UTC is TAI minus a whole number of seconds. From 1972, leap seconds kept UTC within 0.9 seconds of the Earth's rotation. Twenty-seven have been added, the last at the end of December 31, 2016, which is why UTC is now 37 seconds behind TAI. GPS time, which matched UTC in 1980 and ignores leap seconds, runs 18 seconds ahead.

Leap seconds are now being retired. In 2022 the General Conference on Weights and Measures decided to widen the allowed gap between UTC and Earth rotation by 2035, and in October 2026 its 28th meeting fixed the details in Resolution 5: from 20 May 2027 UTC runs continuously, and the permitted gap to Earth rotation grows to one hour. Eastern Time will not notice. Its offset stays exactly −5 or −4 hours from UTC.

Who uses UTC instead of Eastern Time?

  • Aviation: flight plans, air traffic control, weather reports and NOTAMs are in UTC worldwide. A flight leaving New York at 9:00 AM EDT is planned for 1300Z.
  • Weather forecasting: forecast model runs are named by their UTC start time, so the "00Z run" starts from 00:00 UTC – 7:00 PM EST or 8:00 PM EDT.
  • Computing: Unix time counts seconds from 00:00:00 UTC on January 1, 1970, and servers, logs and APIs usually record UTC.
  • Military, shipping and amateur radio: all log in UTC so that every station shares one clock regardless of where it is.

For the UK's civil time, which leaves GMT in summer, see EST to GMT.

Convert any Eastern time to UTC

UTC is preselected. Enter a time and date in ET; the converter picks EST or EDT for that date and shows the result on a 12-hour clock. More zones are on the time zone converter.

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Frequently asked questions

What is 00:00 UTC in Eastern Time?

7:00 PM EST or 8:00 PM EDT on the previous day. For example, 00:00 UTC on July 4 is 8:00 PM EDT on July 3.

Is UTC the same as GMT?

On the clock, yes: both read the same time. UTC is the atomic standard, while GMT is a time zone name used by the UK in winter and by some countries all year. London leaves GMT in summer, which is why EST to GMT has its own page.

What does 1400Z mean?

14:00 UTC, written in the aviation and military style. It is 9:00 AM EST in winter or 10:00 AM EDT in summer.

Is UTC−5 always the same as EST?

The offset is the same, but not every UTC−5 place follows Eastern Time in summer. Colombia, Peru, Panama and Jamaica stay at UTC−5 all year, while the Eastern Time Zone moves to UTC−4 – see places at UTC−5.

How do I convert a UTC timestamp to Eastern Time in code?

Use a library that knows the IANA database. In JavaScript, new Date('2027-01-15T14:00:00Z').toLocaleString('en-US', {timeZone: 'America/New_York'}) returns "1/15/2027, 9:00:00 AM".

Explore

EST to GMT

London time, BST and the mismatch weeks.

Glossary

Offsets, IANA zones and other terms.

EST & EDT

Eastern Time's two offsets explained.