How do you convert EST to GMT?

Use GMT = EST + 5 hours. For 21:00 EST that gives 02:00 GMT.

What does 21:00 EST actually mean?

It sits between 17 and 23 EST; the table on this page shows how those compare.

21:00 EST to GMT

02:00 GMT

21:00 Eastern Standard Time equals 02:00 Greenwich Mean Time.

These are standard-time offsets, which never change. What changes is which one a place observes: New York is on EST in winter but EDT (an hour later) during daylight saving, and the UK is on GMT in winter and BST in summer. If you mean "the time in New York right now", use the full converter — it reads live offsets.

How the conversion works

This one is a formula rather than a single multiplier:

GMT = EST + 5 hours → 02:00 GMT

Going the other way: 02:00 GMT to EST.

Convert a different time zone

EST =02:00 GMT

Open the full time zone converter for every other unit.

Nearby values

EST	GMT
17:00 EST	22:00 GMT
18:00 EST	23:00 GMT
19:00 EST	00:00 GMT
20:00 EST	01:00 GMT
22:00 EST	03:00 GMT
23:00 EST	04:00 GMT

Questions

What is 21:00 EST in GMT?: 21:00 EST is 02:00 GMT.
How do you convert EST to GMT?: Use GMT = EST + 5 hours. For 21:00 EST that gives 02:00 GMT.
What does 21:00 EST actually mean?: It sits between 17 and 23 EST; the table on this page shows how those compare.