What is the time difference between Tokyo and Tehran?

Tokyo (JST, UTC+9) is 5 hours 30 minutes ahead of Tehran (IRST, UTC+3:30) year-round. Neither Japan nor Iran currently observes Daylight Saving Time.

Does Tokyo observe Daylight Saving Time?

No. Japan abolished DST in 1952 and has not used it since. Tokyo stays on JST (UTC+9) all year.

Does Iran observe Daylight Saving Time?

No. Iran ended seasonal clock changes in 2022 and now remains on IRST (UTC+3:30) year-round.

What are the best meeting times when calling from Tokyo to Tehran?

The overlap between standard business hours (09:00–18:00) occurs in the Tokyo afternoon. Tokyo at 14:30–18:00 JST corresponds to Tehran at 09:00–12:30 IRST, covering Tehran's morning workday.

Is this tool accurate for scheduling?

Yes. It uses the IANA timezone database embedded in your browser — the same source used by operating systems and calendar apps worldwide. Accuracy depends on your device clock being synchronized via NTP, which most devices do automatically.

IRST stands for Iran Standard Time (UTC+3:30). Iran uses this half-hour UTC offset year-round.

Time Difference: Tokyo to Tehran

See the current time in Tokyo and Tehran side by side, with the live UTC offset — Tokyo is UTC+9 and Tehran is UTC+3:30 year-round.

Tokyo, Japan

--:--:--

JST UTC+9

Tehran, Iran

--:--:--

IRST UTC+3:30

Current Offset

+5h 30m

Tokyo is 5 hours 30 minutes ahead of Tehran

Convert Tokyo Time to Tehran Time

Based on the current offset — updates automatically

Tokyo (JST)	Tehran (IRST)

Meeting Overlap Finder

Business hours (09:00–18:00) highlighted — best overlap shaded

Tokyo (JST)	Tehran (IRST)	Status

Summary

See the current time in Tokyo and Tehran side by side, with the live UTC offset — Tokyo is UTC+9 and Tehran is UTC+3:30 year-round.

How it works

Your browser reads the current moment from your device clock.
It converts that moment to Asia/Tokyo time (JST, UTC+9) using the IANA timezone database built into modern browsers.
The same moment is converted to Asia/Tehran time (IRST, UTC+3:30 year-round).
The UTC offsets of both cities are compared to calculate the exact hour and minute difference.
All three values — Tokyo time, Tehran time, and the offset — refresh every second.
The displayed offset is derived from the browser's current IANA timezone data.

Use cases

Scheduling video calls between Tokyo and Tehran offices.
Checking if a colleague in Tehran is still at their desk.
Planning Japan-Iran travel and arrival time comparisons.
Remote teams coordinating daily standups across Japan and Iran.
Finding overlapping business hours for Tokyo-Tehran meetings.
Converting a Tokyo meeting time to its Tehran equivalent.
Journalists in Tokyo checking broadcast times for live Iran events.
Students and teachers arranging online lessons between Japan and Iran.

Frequently Asked Questions

Last updated: 2026-09-19 · Reviewed by Nham Vu