Time in ULAST and IDLW
The time difference between Ulaanbaatar Summer Time (ULAST) and International Date Line West Time (IDLW) is 21 hours. International Date Line West Time is 21 hours behind Ulaanbaatar Summer Time.
This means 9am ULAST is 12pm IDLW (previous day) and 5pm ULAST is 8pm IDLW (previous day).
Ulaanbaatar Summer Time
- The current local time in ULAST is 9:42 pm (July 18, 2026)
- ULAST time zone offset is UTC+09:00
International Date Line West Time
- The current local time in IDLW is 12:42 am (July 19, 2026)
- IDLW time zone offset is UTC-12:00
How to convert Ulaanbaatar Summer Time to International Date Line West Time?
Subtract 21 hours from Ulaanbaatar Summer Time to get International Date Line West Time.
Time in ULAST
00:00
Time in IDLW
00:00
Use the slider above to convert Ulaanbaatar Summer Time to International Date Line West Time and view the day and night map at different times.
Day–night colors on the map:
Day
Civil twilight
Nautical twilight
Astronomical twilight
NightTime Conversion Chart
| ULAST | IDLW |
|---|---|
| 12am | 3am |
| 1am | 4am |
| 2am | 5am |
| 3am | 6am |
| 4am | 7am |
| 5am | 8am |
| 6am | 9am |
| 7am | 10am |
| 8am | 11am |
| 9am | 12pm |
| 10am | 1pm |
| 11am | 2pm |
| 12pm | 3pm |
| 1pm | 4pm |
| 2pm | 5pm |
| 3pm | 6pm |
| 4pm | 7pm |
| 5pm | 8pm |
| 6pm | 9pm |
| 7pm | 10pm |
| 8pm | 11pm |
| 9pm | 12am |
| 10pm | 1am |
| 11pm | 2am |