Convert Iran Standard Time to Atlantic Standard Time
Instantly convert Iran Standard Time (IRST) to Atlantic Standard Time (AST) with our free online calculator.
Iran Standard Time
08:50:59 AM
Wed, Jun 24 (IRST)
Atlantic Standard Time
01:20:59 AM
Wed, Jun 24 (AST)
Convert a Specific Time
24-Hour Comparison
| IRST | AST |
|---|---|
| 12:00 AM | 4.5:00 PM(-1d) |
| 1:00 AM | 5.5:00 PM(-1d) |
| 2:00 AM | 6.5:00 PM(-1d) |
| 3:00 AM | 7.5:00 PM(-1d) |
| 4:00 AM | 8.5:00 PM(-1d) |
| 5:00 AM | 9.5:00 PM(-1d) |
| 6:00 AM | 10.5:00 PM(-1d) |
| 7:00 AM | 11.5:00 PM(-1d) |
| 8:00 AM | 0.5:00 AM |
| 9:00 AM | 1.5:00 AM |
| 10:00 AM | 2.5:00 AM |
| 11:00 AM | 3.5:00 AM |
| 12:00 PM | 4.5:00 AM |
| 1:00 PM | 5.5:00 AM |
| 2:00 PM | 6.5:00 AM |
| 3:00 PM | 7.5:00 AM |
| 4:00 PM | 8.5:00 AM |
| 5:00 PM | 9.5:00 AM |
| 6:00 PM | 10.5:00 AM |
| 7:00 PM | 11.5:00 AM |
| 8:00 PM | 0.5:00 PM |
| 9:00 PM | 1.5:00 PM |
| 10:00 PM | 2.5:00 PM |
| 11:00 PM | 3.5:00 PM |
How to Convert Iran Standard Time to Atlantic Standard Time
Formula
To convert Iran Standard Time (IRST) to Atlantic Standard Time (AST): Convert IRST to AST
About Iran Standard Time (IRST)
Iran Standard Time (IRST, IANA: Asia/Tehran) is the civil time of the Islamic Republic of Iran, set at UTC+3:30 — one of the world's few 30-minute-offset time zones. IRST observes Daylight Saving Time (switching to IRDT = UTC+4:30) from the last Wednesday of the Iranian month of Farvardin (~March 22) to the last Wednesday of Shahrivar (~September 22) per Iranian government calendar (the country abolished DST in 2022 then partially reinstated it for energy savings — the schedule is subject to change by Iranian Parliament Majlis decree). The 30-minute offset is preserved because Iran's central meridian is approximately 52.5°E, between UTC+3 and UTC+4 standard zones, and the Iranian Solar Hijri calendar has its own astronomical traditions for time-keeping. IRST serves approximately 88 million Iranian people across 31 provinces. Major cities: Tehran (8.7M city, 13M metro — capital), Mashhad (3.1M), Isfahan (2.2M), Karaj (1.6M), Shiraz (1.6M), Tabriz (1.6M), Qom (1.2M). Other 30/45-minute offset zones: India (UTC+5:30), Nepal (UTC+5:45), Myanmar (UTC+6:30), Newfoundland (UTC-3:30), Afghanistan (UTC+4:30), Marquesas (UTC-9:30). Affects: Tehran Stock Exchange (TSE) trading, Iranian Solar Hijri New Year Nowruz celebrations.
About Atlantic Standard Time (AST)
Atlantic Standard Time (AST, IANA: America/Halifax, America/Puerto_Rico) is the time zone for the Canadian Maritime provinces and most of the Caribbean, set at UTC-4:00. AST is observed in: Nova Scotia, New Brunswick, Prince Edward Island, Labrador (partially), Newfoundland's Labrador portion, eastern Quebec, Puerto Rico, US Virgin Islands, Bermuda, Anguilla, Antigua, Aruba, Barbados, British Virgin Islands, Curaçao, Dominica, Grenada, Guadeloupe, Martinique, Saint Lucia, Saint Vincent, Trinidad and Tobago, and Venezuela (since 2007). Canadian Maritime provinces observe AST in winter and switch to ADT = UTC-3:00 in summer per the Energy Policy Act-aligned Canadian schedule. The Caribbean territories (Puerto Rico, USVI, Bermuda) and US territories observe AST year-round without DST per their territorial governments. AST is the same offset as EDT (Eastern Daylight Time) during US summer months, so Halifax and New York are on the same clock in summer but Halifax is one hour ahead in winter.