Three numbers. The ones that decide the meeting.
When the world meets at work.
Read the day in both zones.
Quick answers. Before you book the call.
What's the time difference between Houston and Tehran?
Houston is 8.5 hours ahead of Tehran. Houston runs on GMT-5 and Tehran on GMT+3:30. The gap can shift by an hour when either side enters or leaves daylight saving — the live clocks above always reflect the current offset.
When's the best time to schedule a meeting?
Standard 09:00–17:00 workdays don't intersect. Most teams compromise with one side meeting early (before 09:00) or late (after 17:00).
Does daylight saving time change the difference?
Yes, if either city observes DST. When one side shifts and the other doesn't, the gap changes by one hour. The DST badges under each clock show whether each zone is currently shifted and when the next transition lands.
How far is Houston from Tehran?
About 11,950 km as the crow flies (great-circle distance). A non-stop commercial flight cruises that in roughly 14h 33m, not counting airport time, winds, or routing around restricted airspace.
Can I send this meeting time as a calendar invite?
Yes. Pick a time on the slider above, open the meeting card, customize the title and duration, then download the .ics file. It imports cleanly into Google Calendar, Outlook, and Apple Calendar with the correct timezone attached.