Singapore is 15 to 16 hours ahead of San Francisco, depending on the time of year. If you are both awake 7 am to 11 pm, a January weekday gives you 8 hours awake at the same time, though none of them is outside a 9-to-5 for both of you (in July: 8 hours shared, 2 hours free). Here are the good ones.
Singapore is 16 hours ahead of San Francisco that week. On a weekday you are both awake for 8 hours, but none of them is outside work for both of you, so a lunch break or a commute has to do the work.
Worked out for the week of 11 January 2027 (11 Jan – 17 Jan), in San Francisco time, with each zone’s own daylight-saving rules for those dates. Singapore awake 7 am – 11 pm, working 9 am – 5 pm weekdays; San Francisco awake 7 am – 11 pm, working 9 am – 5 pm weekdays.
A weekday, in San Francisco timeboth awake
San Franciscoawake 7 am – 11 pm
Singaporeawake 3 pm – 7 am San Francisco time
7a10a1p4p7p10p1a4a7a
Best on a weekday
8 – 10 pm San Francisco
noon – 2 pm Singapore · San Francisco evening, Singapore lunchtime (their next day) · during Singapore’s lunch break
Another weekday option
5 – 7 pm San Francisco
9 – 11 am Singapore · San Francisco early evening, Singapore morning (their next day) · during Singapore’s work hours
The long weekend call
Sat 6 – 9 pm San Francisco
Sun 10 am – 1 pm Singapore · San Francisco early evening, Singapore morning
The week · San Francisco time, 11 Jan – 17 Jan
7a
8a
9a
10a
11a
12p
1p
2p
3p
4p
5p
6p
7p
8p
9p
10p
Mon
11p
12a
1a
2a
3a
4a
5a
6a
7a
8a
9a
10a
11a
12p
1p
2p
Tue
11p
12a
1a
2a
3a
4a
5a
6a
7a
8a
9a
10a
11a
12p
1p
2p
Wed
11p
12a
1a
2a
3a
4a
5a
6a
7a
8a
9a
10a
11a
12p
1p
2p
Thu
11p
12a
1a
2a
3a
4a
5a
6a
7a
8a
9a
10a
11a
12p
1p
2p
Fri
11p
12a
1a
2a
3a
4a
5a
6a
7a
8a
9a
10a
11a
12p
1p
2p
Sat
11p
12a
1a
2a
3a
4a
5a
6a
7a
8a
9a
10a
11a
12p
1p
2p
Sun
11p
12a
1a
2a
3a
4a
5a
6a
7a
8a
9a
10a
11a
12p
1p
2p
Columns are San Francisco hours; the small figure in each cell is the time in Singapore. both freeboth awake, one at workSingapore asleep
The Singapore–San Francisco gap through 2027
Dates
Difference
1 January – 13 March
Singapore is 16 hours ahead of San Francisco
14 March – 6 November
Singapore is 15 hours ahead of San Francisco
7 November – 31 December
Singapore is 16 hours ahead of San Francisco
The week grid and call windows were worked out for 11 Jan to 17 Jan 2027 with the IANA time-zone rules for Asia/Singapore (Singapore) and America/Los_Angeles (San Francisco). That week San Francisco is on standard time and Singapore keeps the same time all year. The table uses the same rules for every day of 2027. The finder above recalculates for the current week in your browser.
When it is … in San Francisco
In San Francisco
Singapore, January
Singapore, July
7 am
11 pm
10 pm
9 am
1 am (next day)
midnight (next day)
11 am
3 am (next day)
2 am (next day)
1 pm
5 am (next day)
4 am (next day)
3 pm
7 am (next day)
6 am (next day)
5 pm
9 am (next day)
8 am (next day)
7 pm
11 am (next day)
10 am (next day)
9 pm
1 pm (next day)
noon (next day)
Wednesday times. Send times as “your 8 pm” or “my 8 pm” so nobody has to guess whose clock you mean.
Stop doing the math every day
The Long Goodbye keeps your person’s local time and time of day on your home-screen widget and lock screen, so you can see whether it is morning coffee or midnight in Singapore before you call. A “thinking of you” tap lights up their widget, and a countdown keeps the next visit in view.
What is the time difference between Singapore and San Francisco?
Singapore is 15 to 16 hours ahead of San Francisco, depending on the time of year. In 2027 it is 16 hours from 1 January to 13 March and from 7 November to 31 December; 15 hours from 14 March to 6 November.
What is the best time to call Singapore from San Francisco?
In January, the easiest two hours on a weekday are 8 – 10 pm San Francisco, which is noon – 2 pm Singapore: San Francisco evening, Singapore lunchtime, the next day there, during Singapore’s lunch break. At the weekend, Sat 6 – 9 pm San Francisco (Sun 10 am – 1 pm Singapore) gives you a longer call. Change the awake and work hours in the finder on this page to fit your own days.
How many waking hours do Singapore and San Francisco share?
If both of you are awake from 7 am to 11 pm, you share 8 hours on a January weekday, but none of them falls outside 9-to-5 working hours in both places; in July it is 8 hours shared and 2 hours free.
Does daylight saving time change the call times?
Yes. In 2027 San Francisco changes its clocks on 14 March and 7 November and Singapore does not change its clocks, so a call you keep at the same time in San Francisco moves by an hour in Singapore on those dates. Check the table on this page and agree the new time out loud after each change.