Convert a time between timezones
Pick two zones and a time. Daylight saving is applied for the date you choose, not assumed — which is why the answer sometimes moves during the year.
Timezone converter
Daylight saving depends on the date, so changing it can change the answer.
- Difference
- —
- From zone
- —
- To zone
- —
| From | To |
|---|
Popular conversions
Each of these has its own page with the full hour-by-hour table:
Why the gap between two zones is not a fixed number
It is tempting to memorise that London is five hours ahead of New York, or that Sydney is eighteen ahead of Los Angeles, and treat those as constants. They are not. The offset each zone has from UTC changes when that country starts or ends daylight saving, and no two countries do it on the same schedule.
The United States moves on the second Sunday of March and the first Sunday of November. The European Union moves on the last Sundays of March and October. For the two or three weeks between the American and European changes, the gap between New York and London is four hours rather than five — long enough that a recurring meeting drifts and nobody can quite explain why. Meanwhile India, Japan, Singapore, and most of Asia never change at all, so their difference from Europe and America moves twice a year without their own clocks moving once.
Every conversion on this page is computed for the specific date in the date field, which is the only way to get this right. That is also why the abbreviations here resolve to geographic zones rather than fixed offsets — "PST" means America/Los_Angeles, and the tool reports whichever of PST or PDT is genuinely in force.
The abbreviation problem
Timezone abbreviations are ambiguous in ways that cause real scheduling errors. IST is Indian Standard Time, Irish Standard Time, and Israel Standard Time. CST is US Central, China Standard, and Cuba Standard. BST is British Summer Time and also Bougainville Standard Time. There is no registry that resolves these, and no way for software to disambiguate them from the letters alone.
The practical advice: when writing a time down for someone else, give the city or the UTC offset rather than the abbreviation. "15:00 UTC" and "15:00 London" are both unambiguous; "15:00 GMT" in July is very probably wrong by an hour, because the UK is on BST then.
Scheduling for more than two zones
This page converts between a pair. When you need to find a slot that works for a whole group, the main comparison grid shows every participant's local time side by side with the workable hours marked, and the best-time finder ranks the candidate slots so you can see which hour costs the fewest people their evening.
Common questions
How many hours ahead is EST from PST?
Three. US Eastern time is always three hours ahead of US Pacific, and that gap is unusually reliable because both zones change to and from daylight saving on the same dates — so the difference holds all year even though the offsets themselves move. Most zone pairs are not like this. Any pair spanning the Atlantic or the equator has a gap that changes several times a year, which is why this page computes the difference for a specific date rather than storing a fixed number.
Why does the difference between two zones change during the year?
Because the countries involved start and end daylight saving on different dates, and some do not observe it at all. The United States springs forward on the second Sunday in March; Europe waits until the last Sunday in that month. For those two or three weeks the gap between New York and London is four hours instead of the usual five. India, Japan, and most of Asia never change at all, so their difference from any European or American zone moves twice a year without their clocks moving once. Every conversion here is computed for the date shown for exactly this reason.
Is PST the same as PDT?
Not literally, though people use PST to mean both. PST is UTC−8 and applies in winter; PDT is UTC−7 and applies from March to November. In practice "PST" is used year-round to mean US Pacific time, so that is how it is treated here — the zone is resolved to America/Los_Angeles and shows whichever offset is actually in force on the date you pick. The same applies to EST and EDT, CST and CDT, GMT and BST. Anything that pins these to a fixed offset is wrong for a good part of the year.
What is the difference between GMT and UTC?
For everyday purposes they name the same instant, but they behave differently on this site and the distinction matters. UTC is a fixed reference that never changes, ever. GMT is used colloquially to mean UK time, which is GMT in winter and shifts to BST — one hour ahead — from late March to late October. So a meeting quoted in "GMT" during the British summer is very often actually BST, an hour off. This page treats GMT as UK time for that reason, and lists UTC separately as the fixed reference it is.
How do I convert a time for a specific date?
Change the date field. It defaults to today, and it exists precisely because the answer differs — a call scheduled for 20 March may land on a different local hour than the identical call two weeks later, if one of the two zones changed to summer time in between. Anyone scheduling recurring meetings across the Atlantic runs into this twice a year, when a slot that worked for months suddenly moves by an hour for one side only.
Does this handle half-hour timezones?
Yes. India is UTC+5:30, Nepal is UTC+5:45, and parts of Australia and Canada sit on half-hour offsets too. The conversion reports minutes separately rather than assuming whole hours, so converting to Indian Standard Time gives you 14:30 rather than a rounded 14:00 or 15:00. Assuming whole hours is a common shortcut in scheduling code and it is wrong for a substantial share of the world's population.