IST to IRST Time Zone Converter — Time Difference Between Colombo and Tehran
Drag the slider or click the time display to type a specific hour and instantly convert IST to IRST. The time difference between Colombo and Tehran is 2 hours — Tehran (IRST) is behind Colombo (IST) (UTC+5:30 vs UTC+3:30); for example, 9:00 AM IST = 7:00 AM IRST; to convert, subtract 2 hours. Use this IST to IRST time zone converter to check the live current time in both cities, browse the 24-hour IST to IRST conversion table, plan international meetings, find the best overlap hours, and account for daylight saving time changes automatically.
IST
India Standard Time
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IRST
Iran Standard Time
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IST to IRST Time Zone Difference — Hour-by-Hour Conversion Table
Scan each row to convert any IST time to IRST and find the exact time difference between Colombo and Tehran hour by hour. Amber-highlighted rows mark standard daytime business hours, making it easy to spot overlapping work windows for scheduling international meetings or remote team calls. Tap the arrows to jump between days, click "Today" to reset, and all daylight saving time transitions are handled automatically.
| IST (Colombo) | IRST (Tehran) |
|---|
What Time Is It Now in Colombo?
Live current local time in Colombo, Sri Lanka — IST (UTC+5:30). Updates every second.
What Time Is It Now in Tehran?
Live current local time in Tehran, Iran — IRST (UTC+3:30). Updates every second.
IST to IRST Quick Reference
Common business hours in Colombo converted to Tehran local time — handy for scheduling video calls, client meetings, and international conference calls.
IST & IRST Meeting Planner — Best Overlapping Hours
Use the color-coded conversion table above to find overlapping business hours between Colombo and Tehran. Amber rows mark standard daytime work hours (8 AM–6 PM local time) — pick a slot that falls in amber on both sides for a meeting time that works for everyone. Since IST (UTC+5:30) is 2 hours behind IRST (UTC+3:30), this time zone meeting planner is ideal for scheduling international calls, remote team standups, and cross-border project syncs.
Why Trust This Colombo to Tehran Time Zone Converter?
ConvertFlash uses the IANA Time Zone Database — the same authoritative source that powers your phone, browser, and every major operating system — so every Colombo to Tehran conversion handles daylight saving time transitions, half-hour UTC offsets, and historical time zone changes automatically. The live world clock updates every second, and the hour-by-hour conversion table regenerates correctly for any past or future date you select, making it reliable for both real-time checks and advance international scheduling.
IST — India Standard Time
Colombo, Sri Lanka — UTC offset UTC+5:30
- Abbreviation
- IST
- UTC Offset
- UTC+5:30
- City
- Colombo
- Country
- Sri Lanka
IRST — Iran Standard Time
Tehran, Iran — UTC offset UTC+3:30
- Abbreviation
- IRST
- UTC Offset
- UTC+3:30
- City
- Tehran
- Country
- Iran