Lang Son runs on UTC+7 every day of the year, with no daylight saving time.
Lang Son and your time
Lang Son at a glance
| Country | Vietnam |
|---|---|
| Region | Lạng Sơn Province |
| Time zone | Asia/Ho_Chi_Minh |
| UTC offset now | UTC+7 |
| Daylight saving time | Not observed |
| Coordinates | 21.85° N, 106.76° E |
Time zone in Lang Son
The clocks in Lang Son follow Asia/Ho_Chi_Minh and keep UTC+7 through every season. No daylight saving time has been recorded here since 1970.
Lang Son is on the same time as the rest of Vietnam, including the capital, Hanoi.
Clock changes in Lang Son, 2026 and 2027
No clock changes are scheduled in Lang Son for 2026 or 2027.
Lang Son time compared with major cities
A 9:00 AM start in Lang Son is 9:00 PM (previous day) in New York, 1:00 PM in Sydney and 6:00 PM (previous day) in Los Angeles.
| City | Time now | Difference now | In January | In July | Shared office hours |
|---|---|---|---|---|---|
| New York (United States) | --:-- | 12 h behind | 12 h behind | 11 h behind | None |
| Los Angeles (United States) | --:-- | 15 h behind | 15 h behind | 14 h behind | None |
| London (United Kingdom) | --:-- | 7 h behind | 7 h behind | 6 h behind | 1 h |
| Paris (France) | --:-- | 6 h behind | 6 h behind | 5 h behind | 2 h |
| Dubai (United Arab Emirates) | --:-- | 3 h behind | 3 h behind | 3 h behind | 5 h |
| Mumbai (India) | --:-- | 1 h 30 min behind | 1 h 30 min behind | 1 h 30 min behind | 6 h 30 min |
| Singapore | --:-- | 1 h ahead | 1 h ahead | 1 h ahead | 7 h |
| Tokyo (Japan) | --:-- | 2 h ahead | 2 h ahead | 2 h ahead | 6 h |
| Sydney (Australia) | --:-- | 4 h ahead | 4 h ahead | 3 h ahead | 4 h |
| UTC | --:-- | 7 h behind | 7 h behind | 7 h behind | 1 h |
Because Lang Son keeps one offset all year, any change in the gap comes from the other city’s daylight saving time. Compare the January and July columns.
Shared office hours counts the time when the clock reads between 9 AM and 5 PM in both cities on the same day.
Sunrise and sunset in Lang Son
Today
| Sunrise | --:-- |
|---|---|
| Sunset | --:-- |
| Day length | -- |
| Solar noon | --:-- |
Day length barely moves in Lang Son, from 10 hours 48 minutes to 13 hours 28 minutes. Sunrise and sunset shift by less than an hour across the year.
Daylight through the year in Lang Son
| Date | Sunrise | Sunset | Day length | |
|---|---|---|---|---|
| March equinox | March 20 | 5:57 AM | 6:04 PM | 12 h 7 min |
| June solstice | June 21 | 5:11 AM | 6:39 PM | 13 h 28 min |
| September equinox | September 23 | 5:42 AM | 5:49 PM | 12 h 7 min |
| December solstice | December 22 | 6:27 AM | 5:15 PM | 10 h 48 min |
When the sun is highest in Lang Son
Lang Son lies close to the centre of its time zone, so the sun is highest at about 11:55 AM on standard time, close to clock noon.
Cities near Lang Son
Distance is not the same as time: Pingxiang (China) lies just 27 km (17 mi) away, yet its clock is 1 hour ahead of Lang Son.
| City | Distance | Time now | Difference |
|---|---|---|---|
| Pingxiang (China) | 27 km (17 mi) | --:-- | 1 h ahead |
| Chũ | 57 km (35 mi) | --:-- | Same time |
| Chongzuo (China) | 86 km (53 mi) | --:-- | 1 h ahead |
| Bắc Giang | 87 km (54 mi) | --:-- | Same time |
| Đông Triều | 89 km (56 mi) | --:-- | Same time |
| Uông Bí | 91 km (57 mi) | --:-- | Same time |
| Thai Nguyen | 99 km (61 mi) | --:-- | Same time |
| Chí Linh | 99 km (61 mi) | --:-- | Same time |
More cities in Vietnam
All time zones and cities in Vietnam
Tools for time in Lang Son
- Convert a time to or from Lang Son: pick a date and time and see it in every city on your list.
- Add Lang Son to your world clock to keep it next to your own time.
- Find a meeting time that falls inside office hours in Lang Son and the other cities you work with.
- Open a full-screen clock for your own time zone.
Frequently asked questions
What time zone is Lang Son in?
Lang Son uses the Asia/Ho_Chi_Minh time zone, which is UTC+7 all year.
Does Lang Son use daylight saving time?
No. Lang Son stays on UTC+7 all year, so the time difference to places without daylight saving time never changes.
What is the time difference between Lang Son and New York?
Lang Son is 12 hours ahead of New York in January and 11 hours ahead of New York in July, because New York moves its clocks for daylight saving time and Lang Son does not.
Is Lang Son on the same time as Hanoi?
Yes. Lang Son and Hanoi both use UTC+7 right now.
How long is the longest day in Lang Son?
About 13 hours 28 minutes, around the June solstice. The shortest day, around the December solstice, has about 10 hours 48 minutes of daylight.
Time zone rules: IANA tz database, version 2026e. Place names and coordinates: GeoNames. Sunrise and sunset are calculated from the coordinates and can differ by a minute or two from local almanacs.