GMT to EST converter

Converting from GMT to EST is one subtraction: take any GMT time and remove five hours. The harder part is remembering that the two sides change their clocks on different dates, so for a few weeks each year the gap is four hours, not five.

How far ahead is GMT of EST?

Greenwich Mean Time sits at UTC+0 and US Eastern Standard Time at UTC-5, a clean five-hour gap. In summer the labels change — the UK uses British Summer Time (BST, UTC+1) and the US East uses Eastern Daylight Time (EDT, UTC-4) — but because both spring forward, the difference stays at roughly five hours.

The bottom two rows are the brief out-of-sync periods each spring and autumn, when one side has changed its clocks and the other has not. The rest of the year the gap is a steady five hours.

GMT to EST conversions

Subtract five hours from GMT to get EST. Here are the times that come up most often.

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Because GMT leads EST by five hours, the overlap that suits both sides is the UK afternoon. By the time the East Coast is settling in for the morning, the UK is well into its working day, and the two stay aligned until the UK winds down.

Aim for 2:00–5:00 PM GMT (9:00 AM–12:00 noon EST) and you catch both sides at their desks. For the longer story of this corridor, see our London to New York time difference guide.

Let Atlas do the subtraction

Doing this five-hour arithmetic by hand is fine once, tiresome daily, and exactly where the daylight-saving slips creep in. Atlas keeps London and New York side by side in your Mac menu bar, shades the hours when both sides are at work, and writes any meeting to your calendar in both local times. One glance shows you the overlap, no counting on your fingers.