AST Time to MST Time Converter

Warning! AST has automatically switched to ADT
MST has automatically switched to MDT

AST stands for Atlantic Standard Time (NOT in use)

ADT stands for Atlantic Daylight Time (in use)

MST stands for Mountain Standard Time (NOT in use)

MDT stands for Mountain Daylight Time (in use)

ADT = UTC - 03:00

06:18:29

Saturday, April 26, 2025

MDT = UTC - 06:00

03:18:29

Saturday, April 26, 2025

ADT(Atlantic Daylight Time) and MDT(Mountain Daylight Time) Mapping Table
Atlantic Daylight Time(ADT)	Mountain Daylight Time(MDT)
00:00	21:00-1 day
01:00	22:00-1 day
02:00	23:00-1 day
03:00	00:00
04:00	01:00
05:00	02:00
06:00	03:00
07:00	04:00
08:00	05:00
09:00	06:00
10:00	07:00
11:00	08:00
12:00	09:00
13:00	10:00
14:00	11:00
15:00	12:00
16:00	13:00
17:00	14:00
18:00	15:00
19:00	16:00
20:00	17:00
21:00	18:00
22:00	19:00
23:00	20:00

ADT(Atlantic Daylight Time)

Atlantic Daylight Time(ADT) is 03:00 hours behind Coordinated Universal(UTC) Time.This timezone is a Daylight Saving Time timezone and is used in: North America

Typical City of ADT (Atlantic Daylight Time)

Canada - Halifax (Summer)
Bermuda - Hamilton (Summer)

MDT(Mountain Daylight Time)

Mountain Daylight Time(MDT) is 06:00 hours behind Coordinated Universal(UTC) Time.This timezone is a Daylight Saving Time timezone and is used in: North America

Typical City of MDT (Mountain Daylight Time)

Canada - Edmonton (Summer)