City comparison · time difference and converter
Tokyo is 16 hours ahead of San Francisco right now. San Francisco sits in United States on Los Angeles; Tokyo sits in Japan on Tokyo. They are roughly 8,275 km apart (5,142 mi), a flight of about 10h 44m. San Francisco's metro holds around 4.7 million people; Tokyo's around 37.4 million.
Slot 1
00:00 / 16:00
San Francisco / Tokyo
Partial overlapSlot 2
09:00 / 01:00
San Francisco / Tokyo
Partial overlapSlot 3
10:00 / 02:00
San Francisco / Tokyo
Partial overlapEach row is one hour in San Francisco. 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.
Juneteenth
San Francisco, United States
Fri, Jun 19
Great-circle distance
8,275 km
(5,142 mi)
Approximate flight
10h 44m
850 km/h cruise + 1h taxi/climb/descent
Jet lag
16h
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 →San Francisco and Tokyo have almost no conventional business-hour overlap. The practical pattern is an evening San Francisco call that reaches Tokyo the next morning, or a late Tokyo call that catches California early. Product, gaming, semiconductor, and venture teams use this route often, but it works best when live meetings are treated as exceptions and written handoffs carry the daily rhythm.
There is no comfortable 9-to-5 overlap. The workable live slot is usually late afternoon or evening in San Francisco and the next morning in Tokyo.
For recurring meetings, choose one humane anchor and rotate the burden monthly. A San Francisco late-afternoon call can work for Tokyo morning, while a Tokyo early-evening call reaches California before work. Keep decision logs tight, because waiting for the next live window can cost a full business day.
This pair is common for hardware supply chains, game launches, and US-Japan startup partnerships. Teams that do it well separate urgent escalation calls from normal status updates and make the handoff document the primary artifact.
The difference between San Francisco and Tokyo is not really a number, it's a daily rhythm. Tokyo is 16 hours ahead of San Francisco on the clock today, but the lived version is that Tokyo is wrapping up the working day while San Francisco 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 San Francisco, the working day picks up earliest in the financial districts — SoMa engineers roll in around 09:30 and Slack stays warm until 19:00. 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. United States shifts the clock on the second Sunday of March and the first Sunday of November; Japan either follows its region's DST pattern or stays put all year. When the two changes are weeks apart, the offset between San Francisco 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 10h 44m 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 16-hour gap costs about 16 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.