1am in Hanoi is 9:30pm in Tehran on the previous day.

Frequently asked

Quick answers about converting between Hanoi and Tehran. Can't find what you need? Email [email protected].

What is the time difference between Hanoi and Tehran?

Hanoi is 3 hours 30 minutes ahead of Tehran right now. We always show the live, daylight-saving-correct difference, so this figure already accounts for whichever side is observing summer time today.

When it's 1am in Hanoi, what time is it in Tehran?

1am in Hanoi is 9:30pm in Tehran on the previous day. It lands deep outside working hours in Tehran — see the best time to meet below for a friendlier slot. Use the hour-by-hour table above to read any other time across.

What's the best time for a call between Hanoi and Tehran?

1pm–5pm in Hanoi lines up with 9:30am–1:30pm in Tehran — both sides are inside a 9-to-5 working day.

Does this account for daylight saving time?

Yes. We track every clock change in both places, so the abbreviations you see — +07:00 and +03:30 — are the ones actually in effect right now, not a fixed all-year value. When either side changes its clocks, this page updates automatically.

Why is the date sometimes different on each side?

When two places are far enough apart, the same moment can fall on different calendar days. That is why some conversions are marked "previous day" or "next day" — it is the same instant in time, read off two clocks that crossed midnight at different points.