City comparison · time difference and converter
Surabaya is 14 hours ahead of San Francisco right now. San Francisco sits in United States on Los Angeles; Surabaya sits in Indonesia on Jakarta. They are roughly 13,530 km apart (8,407 mi), a flight of about 16h 55m. San Francisco's metro holds around 4.7 million people; Surabaya's around 2.9 million.
Slot 1
00:00 / 14:00
San Francisco / Surabaya
Partial overlapSlot 2
01:00 / 15:00
San Francisco / Surabaya
Partial overlapSlot 3
02:00 / 16:00
San Francisco / Surabaya
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.
Pancasila Day
Surabaya, Indonesia · Hari Lahir Pancasila
Mon, Jun 1
Juneteenth
San Francisco, United States
Fri, Jun 19
Great-circle distance
13,530 km
(8,407 mi)
Approximate flight
16h 55m
850 km/h cruise + 1h taxi/climb/descent
Jet lag
14h
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 San Francisco and Surabaya is not really a number, it's a daily rhythm. Surabaya is 14 hours ahead of San Francisco on the clock today, but the lived version is that Surabaya 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 Surabaya is its own story: Surabaya 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. United States shifts the clock on the second Sunday of March and the first Sunday of November; Indonesia 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 Surabaya 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 16h 55m 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 14-hour gap costs about 14 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.