IRST to AST converter

Iran Time (Tehran) to Atlantic Time (Halifax).

IRST3:37 AMSat 31 Oct 2026

→

AST9:07 PMFri 30 Oct 2026

AST is 6 h 30 min behind IRST.

Pick a time in IRST

⇄ AST to IRST

9:00 AM IRST = 2:30 AM AST same day

Best time to meet

The best time to meet is between 4:00 PM and 5:00 PM IRST, which is 9:30 AM to 10:30 AM AST. Both sides are then inside 9 AM to 5 PM.

IRST to AST time table

For 31 Oct 2026. Green rows: both sides between 9 AM and 5 PM.

IRST	AST
12:00 AM IRST	5:30 PM AST previous day
1:00 AM IRST	6:30 PM AST previous day
2:00 AM IRST	7:30 PM AST previous day
3:00 AM IRST	8:30 PM AST previous day
4:00 AM IRST	9:30 PM AST previous day
5:00 AM IRST	10:30 PM AST previous day
6:00 AM IRST	11:30 PM AST previous day
7:00 AM IRST	12:30 AM AST
8:00 AM IRST	1:30 AM AST
9:00 AM IRST	2:30 AM AST
10:00 AM IRST	3:30 AM AST
11:00 AM IRST	4:30 AM AST
12:00 PM IRST	5:30 AM AST
1:00 PM IRST	6:30 AM AST
2:00 PM IRST	7:30 AM AST
3:00 PM IRST	8:30 AM AST
4:00 PM IRST	9:30 AM AST
5:00 PM IRST	10:30 AM AST
6:00 PM IRST	11:30 AM AST
7:00 PM IRST	12:30 PM AST
8:00 PM IRST	1:30 PM AST
9:00 PM IRST	2:30 PM AST
10:00 PM IRST	3:30 PM AST
11:00 PM IRST	4:30 PM AST

Quick answers

9:00 AM IRST = 2:30 AM AST
12:00 PM IRST = 5:30 AM AST
3:00 PM IRST = 8:30 AM AST
5:00 PM IRST = 10:30 AM AST
9:00 AM AST = 3:30 PM IRST
12:00 PM AST = 6:30 PM IRST
5:00 PM AST = 11:30 PM IRST

Does the gap change during the year?

Yes, because of daylight saving. Until 1 Nov 2026: AST is 6 h 30 min behind IRST. From 1 Nov 2026 to 14 Mar 2027: AST is 7 h 30 min behind IRST. From 14 Mar 2027 to 7 Nov 2027: AST is 6 h 30 min behind IRST.

IRST does not change its clocks. AST next changes its clocks on 1 Nov 2026 (back 1 h, to UTC−4), then on 14 Mar 2027 (forward 1 h, to UTC−3).

About IRST and AST

IRST here means Iran Time, the clock in Tehran. Right now it is UTC+3:30. It has no daylight saving.

AST here means Atlantic Time, the clock in Halifax. Right now it is UTC−3. Strictly, AST is the winter name; in summer these places use ADT. This page follows their real clock all year.

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