MDT to AST Converter
Time Difference
Mountain Daylight Time is 3 hours behind Atlantic Daylight Time
7:00 am07:00 in MDT is 10:00 am10:00 in ADT
MDT to AST call time
Best time for a conference call or a meeting is between 8am-4pm in MDT which corresponds to 10am-6pm in AST
7:00 am07:00 Mountain Daylight Time (MDT). Offset UTC -6:00 hours
10:00 am10:00 Atlantic Daylight Time (ADT). Offset UTC -3:00 hours
7:00 am07:00 MDT / 10:00 am10:00 ADT
| MDT | ADT |
|---|---|
| 12am (midnight) | 3am |
| 1am | 4am |
| 2am | 5am |
| 3am | 6am |
| 4am | 7am |
| 5am | 8am |
| 6am | 9am |
| 7am | 10am |
| 8am | 11am |
| 9am | 12pm (noon) |
| 10am | 1pm |
| 11am | 2pm |
| 12pm (noon) | 3pm |
| 1pm | 4pm |
| 2pm | 5pm |
| 3pm | 6pm |
| 4pm | 7pm |
| 5pm | 8pm |
| 6pm | 9pm |
| 7pm | 10pm |
| 8pm | 11pm |
| 9pm | 12am (midnight) |
| 10pm | 1am |
| 11pm | 2am |
| 0:00 | 3:00 |
| 1:00 | 4:00 |
| 2:00 | 5:00 |
| 3:00 | 6:00 |
| 4:00 | 7:00 |
| 5:00 | 8:00 |
| 6:00 | 9:00 |
| 7:00 | 10:00 |
| 8:00 | 11:00 |
| 9:00 | 12:00 |
| 10:00 | 13:00 |
| 11:00 | 14:00 |
| 12:00 | 15:00 |
| 13:00 | 16:00 |
| 14:00 | 17:00 |
| 15:00 | 18:00 |
| 16:00 | 19:00 |
| 17:00 | 20:00 |
| 18:00 | 21:00 |
| 19:00 | 22:00 |
| 20:00 | 23:00 |
| 21:00 | 0:00 |
| 22:00 | 1:00 |
| 23:00 | 2:00 |
Mountain Daylight Time
Offset: MDT is 6 hours behind Greenwich Mean Time (GMT) and is used in North America
Countries: It is used in following countries: Canada, Mexico, United States
Principal Cities: The largest city in the MDT timezone is Calgary from Canada with population about 1.02 million people. Other major cities in the area are Edmonton, El Paso, Denver, Albuquerque
French: HAR - Heure Avancée des Rocheuses
Spanish: MT - Zona Pacífico
Daylight Saving: Mountain Daylight Time (MDT) is a daylight saving/summer timezone, however during winter some places switch clocks for one hour back and observe Mountain Standard Time (MST).
Start: Mountain Daylight Time (MDT) started on Sunday, March 9, 2025 at 2:00 am local time and clocks were set one hour forward to Sunday, March 9, 2025, 3:00 am. Daylight saving starts annually the on second Sunday of March
End: Mountain Daylight Time (MDT) ends on Sunday, November 2, 2025 at 2:00 am local time and clocks are set one hour back to Sunday, November 2, 2025, 1:00 am local standard time instead. Daylight saving ends annually the on first Sunday of November
MDT representations, usage and related time zones
- -06 - basic short
- -0600 - basic
- -06:00 - extended
- -0600 - sign character (-) followed by a four digit time providing hours (06) and minutes (00) of the offset. Indicates six hour and zero minutes time differences to the west of the zero meridian.
- Sierra - Military abbreviation for MDT
- S - short form of 'Sierra'
- America/Boise
- America/Cambridge_Bay
- America/Ciudad_Juarez
- America/Denver
- America/Edmonton
- America/Inuvik
- America/Shiprock
- America/Yellowknife
- Canada/Mountain
- MST7MDT
- Navajo
- US/Mountain
- CST - Central Standard Time
- CT - Central Time
- MDT - Mountain Daylight Time
- EAST - Easter Island Standard Time
- GALT - Galapagos Time
- S - Sierra Time Zone
Atlantic Standard Time
Offset: AST is 4 hours behind Greenwich Mean Time (GMT) and is used in North America
Countries: It is used in following countries: Antigua & Barbuda, Anguilla, Aruba, Barbados, St Barthelemy, Bermuda, Caribbean NL, Canada, Curaçao, Dominica, Dominican Republic, Grenada, Greenland, Guadeloupe, St Kitts & Nevis, St Lucia, St Martin (French), Martinique, Montserrat, Puerto Rico, St Maarten (Dutch), Trinidad & Tobago, St Vincent, Virgin Islands (UK), Virgin Islands (US)
Principal Cities: The largest city in the AST timezone is Santo Domingo from Dominican Republic with population about 2.202 million people. Other major cities in the area are Santiago de los Caballeros, Santo Domingo Oeste, San Juan, Halifax
French: HNA - Heure Normale de l'Atlantique
Spanish: AST - Tiempo Estándar del Atlántico
Daylight Saving: This is a standard time zone, however during summer some places switch clocks for one hour forward when daylight saving comes into effect and observe Atlantic Daylight Time (ADT).
End: Atlantic Standard Time (AST) has ended on Sunday, March 9, 2025 at 2:00 am local time and clocks were set one hour forward to Sunday, March 9, 2025, 3:00 am local daylight time instead. Standard time ends annually the on second Sunday of March.
Start: Atlantic Standard Time (AST) starts on Sunday, November 2, 2025 at 2:00 am local time and clocks are set one hour back to Sunday, November 2, 2025, 1:00 am. Standard time starts annually the on first Sunday of November.
AST representations, usage and related time zones
- -04 - basic short
- -0400 - basic
- -04:00 - extended
- -0400 - sign character (-) followed by a four digit time providing hours (04) and minutes (00) of the offset. Indicates four hour and zero minutes time differences to the west of the zero meridian.
- Quebec - Military abbreviation for AST
- Q - short form of 'Quebec'
- America/Anguilla
- America/Antigua
- America/Aruba
- America/Barbados
- America/Blanc-Sablon
- America/Curacao
- America/Dominica
- America/Glace_Bay
- America/Goose_Bay
- America/Grenada
- America/Guadeloupe
- America/Halifax
- America/Kralendijk
- America/Lower_Princes
- America/Marigot
- America/Martinique
- America/Moncton
- America/Montserrat
- America/Port_of_Spain
- America/Puerto_Rico
- America/Santo_Domingo
- America/St_Barthelemy
- America/St_Kitts
- America/St_Lucia
- America/St_Thomas
- America/St_Vincent
- America/Thule
- America/Tortola
- America/Virgin
- Atlantic/Bermuda
- Canada/Atlantic
- Atlantic Standard Time - UTC -4
- Arabia Standard Time - UTC +3
- Arabian Standard Time - UTC +3
- Argentina Standard Time - UTC -3
- Azores Standard Time - UTC -1
- Apia Standard Time - UTC +13
- AST - Atlantic Standard Time
- EDT - Eastern Daylight Time
- AMT - Amazon Time
- BOT - Bolivia Time
- CDT - Cuba Daylight Time
- CLT - Chile Standard Time
- FKT - Falkland Island Time
- GYT - Guyana Time
- HLV - Hora Legal de Venezuela
- PYT - Paraguay Time
- Q - Quebec Time Zone
- VET - Venezuelan Standard Time