City comparison · time difference and converter
Tokyo is 12 hours ahead of Asuncion right now. Asuncion sits in Paraguay on Asuncion; Tokyo sits in Japan on Tokyo. They are roughly 18,000 km apart (11,185 mi), a flight of about 22h 11m. Asuncion's metro holds around 1.5 million people; Tokyo's around 37.4 million.
Slot 1
00:00 / 12:00
Asuncion / Tokyo
Partial overlapSlot 2
01:00 / 13:00
Asuncion / Tokyo
Partial overlapSlot 3
02:00 / 14:00
Asuncion / Tokyo
Partial overlapEach row is one hour in Asuncion. 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.
Chaco Armistice
Asuncion, Paraguay · Dia de la Paz del Chaco
Fri, Jun 12
Great-circle distance
18,000 km
(11,185 mi)
Approximate flight
22h 11m
850 km/h cruise + 1h taxi/climb/descent
Jet lag
12h
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 Asuncion and Tokyo is not really a number, it's a daily rhythm. Tokyo is 12 hours ahead of Asuncion on the clock today, but the lived version is that Tokyo is wrapping up the working day while Asuncion is still in the morning, and the overlap people actually use is narrow. That gap, more than the raw offset, is what teams have to design around.
In Asuncion, the working day picks up earliest in the financial districts — Asuncion's downtown core wakes early and breaks for lunch at the usual hour. The mood in Tokyo is its own story: Shibuya's office workers leave around 19:00, often heading to izakayas, then home on the last train. 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. Paraguay either observes DST or holds a fixed offset year-round; Japan either follows its region's DST pattern or stays put all year. When the two changes are weeks apart, the offset between Asuncion and Tokyo 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 22h 11m 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 12-hour gap costs about 12 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.