Current time in San Sebastián
Current time
America/Puerto_Rico · AST (UTC-04:00)
Neighbouring days
- Previous day
- Today
- Next day
Sunrise and sunset
- Sunrise
- 06:16
- Sunset
- 18:25
- Solar noon
- 12:20
- Daylight
- 12 h 9 min
- Night
- 11 h 52 min
The local date has changed — reload the page for the new sunrise and sunset.
Today and the next four days
| Date | Sunrise | Sunset | Daylight | Change |
|---|---|---|---|---|
| 06:16 | 18:25 | 12 h 9 min | ||
| 06:16 | 18:24 | 12 h 7 min | -1 min 1 s | |
| 06:17 | 18:23 | 12 h 6 min | -1 min 2 s | |
| 06:17 | 18:22 | 12 h 5 min | -1 min 2 s | |
| 06:17 | 18:21 | 12 h 4 min | -1 min 1 s |
Twilight
| Kind | Begins (morning) | Ends (evening) |
|---|---|---|
| Civil twilight (daylight begins / ends) | 05:54 | 18:46 |
| Nautical twilight | 05:29 | 19:12 |
| Astronomical twilight | 05:04 | 19:37 |
Civil twilight is the period when the sun is within 6 degrees below the horizon — bright enough to see outdoors without lights, and what people usually mean by “it gets light” and “it gets dark”. Nautical uses 12 degrees and astronomical 18 degrees. At high latitudes a band can be absent for a whole day, in which case the row is left blank.
Longest and shortest days in 2026
- Longest day
- 13 h 14 min (20 June 2026)
- Shortest day
- 11 h 2 min (21 December 2026)
Computed from the coordinates of San Sebastián: 18.33662, -66.99018.
Sunrise and sunset are the moments when the centre of the sun is 50 arcminutes below the horizon, which accounts for atmospheric refraction and the sun’s apparent radius — the same convention as common astronomical almanacs. Daylight is sunset minus sunrise; night is taken as 24 hours minus daylight. Elevation, terrain and local weather are not included, so observed times can differ by a minute or two.
Zone details
| Country / region | Puerto Rico |
|---|---|
| Administrative division | San Sebastián |
| IANA time zone | America/Puerto_Rico |
| Current UTC offset | UTC-04:00 |
| Zone abbreviation | AST |
| Population | 11,590 |
| Latitude / longitude | 18.3366200, -66.9901800 |
Daylight saving
San Sebastián does not observe daylight saving and stays on UTC-04:00 all year.
This moment in other formats
| Unix timestamp | 1790002316 |
|---|---|
| ISO 8601 | 2026-09-21T10:51:56-04:00 |
| ISO week | 2026-W39 |
| Day of the year | day 264 of 365 |
| Days left this year | 101 days |
These values update with the clock above and use the local date in San Sebastián.
Difference from a reference city
San Sebastián is 5 hours behind London.
Both places are on the same date right now.
Working-hours overlap with London
About 4 h of overlap each day.
- San Sebastián 09:00–13:00 matches London 14:00–18:00
Working hours are taken as 09:00–18:00 local on each side, using the offsets for today.
Hour-by-hour conversion
Calculated for 2026-09-21 local time in San Sebastián. The two places start and end daylight saving on different dates, so another day can give a different result.
| San Sebastián (source) | London (target) |
|---|---|
| 00:00 | 05:00 |
| 01:00 | 06:00 |
| 02:00 | 07:00 |
| 03:00 | 08:00 |
| 04:00 | 09:00 |
| 05:00 | 10:00 |
| 06:00 | 11:00 |
| 07:00 | 12:00 |
| 08:00 | 13:00 |
| 09:00 | 14:00 |
| 10:00 | 15:00 |
| 11:00 | 16:00 |
| 12:00 | 17:00 |
| 13:00 | 18:00 |
| 14:00 | 19:00 |
| 15:00 | 20:00 |
| 16:00 | 21:00 |
| 17:00 | 22:00 |
| 18:00 | 23:00 |
| 19:00 | 00:00 next day |
| 20:00 | 01:00 next day |
| 21:00 | 02:00 next day |
| 22:00 | 03:00 next day |
| 23:00 | 04:00 next day |
Other cities in Puerto Rico
Cities also on America/Puerto_Rico
How to use this page
The top of the page shows the current date and time in San Sebastián, ticking in the America/Puerto_Rico zone. To convert a specific moment to another city, use the comparison link below, where you can enter a date and time.
How the time is calculated
San Sebastián is bound to the IANA identifier America/Puerto_Rico. The server resolves the UTC offset and daylight saving state for the requested moment and renders the first view; the browser then keeps time in the same zone and re-syncs when the tab comes back to the foreground. No fixed offset stands in for the zone, and no zone is guessed from the city name.
FAQ
- Which time zone is San Sebastián in?
- San Sebastián uses the IANA identifier America/Puerto_Rico, currently UTC-04:00. The same identifier can have different offsets on different dates; the value above is for the current moment.
- Does San Sebastián observe daylight saving time?
- The daylight saving section above answers this from the IANA database: cities that do not observe it show no changeover text, and cities that do show the current state and the next local changeover time.
- What time are sunrise and sunset in San Sebastián today?
- The sunrise and sunset section above gives today’s sunrise, sunset and solar noon along with the length of daylight and night, plus how they change over the next four days. Times are computed from the coordinates of San Sebastián in the America/Puerto_Rico zone; at high latitudes sunrise or sunset can fall on the adjacent date, which the page marks explicitly.
- How many hours is San Sebastián from London?
- Calculated for the current moment: San Sebastián is 5 hours behind London. The section above also shows each side’s local date at that same instant. Because the two places start and end daylight saving on different dates, the gap changes during the year — use the fixed-date mode in the comparison tool for another date.
- Can a cached page show the wrong time?
- No. The first render uses server time as a starting value, and as soon as the page loads the browser recomputes the current moment for America/Puerto_Rico and takes over the clock, so a cache hit still shows the time at which you opened it.