IRST to PST Time Converter

When it is 9:00 AM IRST, it is 10.5:00 PM PST. Pacific Standard Time (PST, UTC-8) is 11.5 hours behind Iran Standard Time (IRST, UTC+3:30). There is no full 9–5 overlap between IRST and PST — teams typically rotate early or late meetings.

IRST to PST Conversion Table

Major Cities Using IRST and PST

Iran Standard Time (IRST): Tehran, Mashhad, Isfahan.

Pacific Standard Time (PST): Los Angeles, San Francisco, Seattle, Vancouver.

How many hours between IRST and PST?

IRST is UTC+3:30 and PST is UTC-8, a difference of 11.5 hours. PST is behind IRST. This difference can shift by an hour in either direction during Daylight Saving Time transitions — if one zone observes DST and the other doesn't, the offset narrows or widens for part of the year.

Business Hours Overlap: IRST ↔ PST

Assuming a 9:00 AM – 5:00 PM workday on each side, there is no full 9–5 overlap between irst and pst — teams typically rotate early or late meetings. To visualize this instantly for any pair of cities, use the visual meeting planner or the timezone overlap finder — both highlight the green overlap window on a live timeline.

Does IRST observe Daylight Saving Time?

Iran Standard Time (IRST) is based on the Asia/Tehran IANA timezone. DST observance depends on the jurisdiction — for example, most of the continental US switches between standard and daylight time, while India, Japan, and most of Southeast Asia do not observe DST at all. WorldClock.lol uses the authoritative IANA timezone database, so every conversion automatically accounts for the correct DST rules on the date you're converting.

When is 9 AM IRST in PST?

When it is 9:00 AM in Iran Standard Time (IRST, UTC+3:30), it is 10.5:00 PM in Pacific Standard Time (PST). For other times of day, scan the conversion table above or drop into the interactive converter to pick an exact minute. The converter handles both standard and daylight variants correctly.

How to Use This IRST to PST Converter

1. Type or drag any time in the IRST input above — the PST equivalent updates instantly.
2. Check the day indicator. When the converted time crosses midnight, the tool shows +1 day or −1 day so you don't book a meeting on the wrong date.
3. Copy the shareable URL to send the specific conversion to a colleague — the link preserves your exact selection.
4. Switch directions by swapping the input zones, or open PST to IRST for the reverse.

Related IRST Converters

• IRST to EST
• IRST to GMT
• IRST to UTC
• IRST to IST
• IRST to JST
• IRST to CET

Related PST Converters

• EST to PST
• GMT to PST
• UTC to PST
• IST to PST
• JST to PST
• CET to PST

More Time Tools

• All Time Zone Converters — browse every supported pair
• About IRST (Iran Standard Time) — current time, cities, DST rules
• About PST (Pacific Standard Time) — current time, cities, DST rules
• Meeting Planner — find the best time for a multi-city meeting
• Best Time to Call — optimal calling windows between any two cities
• UTC Time Now — the reference point for every conversion
• DST Schedule 2026 — every daylight-saving transition this year