City comparison · time difference and converter
Karaj is 2.5 hours behind Dhaka right now. Dhaka sits in Bangladesh on Dhaka; Karaj sits in Iran on Tehran. They are roughly 4,000 km apart (2,485 mi), a flight of about 5h 42m. Dhaka's metro holds around 22.4 million people; Karaj's around 1.4 million.
Slot 1
12:00 / 09:00
Dhaka / Karaj
Both inside business hoursSlot 2
13:00 / 10:00
Dhaka / Karaj
Both inside business hoursSlot 3
14:00 / 11:00
Dhaka / Karaj
Both inside business hoursEach row is one hour in Dhaka. Green rows are inside business hours in both cities; amber means only one side is at their desk; grey rows fall outside business hours in both.
No public holidays in Bangladesh or Iran this month.
Great-circle distance
4,000 km
(2,485 mi)
Approximate flight
5h 42m
850 km/h cruise + 1h taxi/climb/descent
Jet lag
3h
Roughly 1 day to adjust per timezone crossed
The heatmap gives you the shape of the day. If you need to convert one specific hour — say a customer call or a release window — open the converter with both cities already loaded.
Open in converter →The difference between Dhaka and Karaj is not really a number, it's a daily rhythm. Karaj is 2.5 hours behind Dhaka on the clock today, but the lived version is that Dhaka is ahead in the calendar, so by the time Karaj comes online, half of Dhaka's day is already gone. That gap, more than the raw offset, is what teams have to design around.
In Dhaka, the working day picks up earliest in the financial districts — Dhaka's downtown core wakes early and breaks for lunch at the usual hour. The mood in Karaj is its own story: Karaj settles into the evening at the usual hour, with the local commuter pattern setting the pace. If you are scheduling between the two, the heatmap above marks the rows where both patterns line up.
Daylight saving is the other thing to keep an eye on. Bangladesh either observes DST or holds a fixed offset year-round; Iran either follows its region's DST pattern or stays put all year. When the two changes are weeks apart, the offset between Dhaka and Karaj is one hour off the usual for that stretch — a cliff that catches recurring calendar invites unless your calendar app rebases them automatically. Pin the meeting to a city, not an offset, and the tool handles the rest.
For travellers, the 5h 42m flight is the short version of the story. The longer one is jet lag: roughly one day of adjustment per timezone crossed, which means a trip across the 3-hour gap costs about 3 groggy days on each side. Pilots and cabin crew swear by morning sunlight and an early walk; whatever your routine, the wall-clock numbers above are the source of truth for your first morning in the new city.