Timezone Overlap Calculator
Compare multiple cities and find the best shared working hours across time zones. Great for remote meetings, support handoffs, interviews, and distributed teams.
Working hours are approximated as 09:00–17:00 local time.
All processing happens locally in your browser — nothing is stored or sent to any server.
How to Find Timezone Overlap
- Select the cities or regions you want to compare.
- Read each row to see every location’s local hour across the UTC grid.
- Look for the strongest highlighted blocks to find the best shared meeting windows.
- Use those overlapping hours for calls, planning sessions, handoffs, or standups.
About Cross-Timezone Scheduling
Scheduling across multiple time zones is one of the most common remote-work bottlenecks, and it scales badly: with 2 cities you usually have 6+ hours of mutual workday overlap, but adding a third city often cuts that to 1-2 hours, and a fourth city can eliminate any natural overlap entirely. Distributed teams that span the Americas, Europe, Asia, and Australia typically have to choose between async-first communication or asking specific team members to take regular off-hours calls.
A visual overlap grid surfaces these tradeoffs immediately. Instead of mental math ("if it's 3pm in Berlin, what time is it in Singapore?"), you see all the time zones simultaneously and identify the candidate meeting windows at a glance. The grid uses standard 9-to-5 local working hours per city as the baseline, which captures most realistic scheduling intent.
Common use cases: scheduling team standups across distributed engineering teams, finding interview windows for international candidates, coordinating support handoffs between regional teams, planning client calls across continents, and identifying when an "always-on" service is unstaffed by humans. The tool runs entirely in your browser and supports any number of cities including locations with non-integer UTC offsets like India, Iran, and Newfoundland.
Frequently Asked Questions
How are working hours calculated? ▼
The tool assumes a standard work day of 09:00–17:00 local time for each city, then maps those eight hours onto the universal UTC timeline. Where two or more cities have overlapping UTC hours that are simultaneously inside their local 9-to-5 windows, you get a viable shared meeting slot.
Does it support half-hour and quarter-hour offsets? ▼
Yes. India (UTC+5:30), Iran (UTC+3:30), Newfoundland (UTC-3:30), parts of Australia (UTC+9:30), and Nepal (UTC+5:45) are all supported. The grid renders these correctly so meetings scheduled for, say, 14:30 in Mumbai map back to the right slot for London or New York.
Does it account for daylight saving time? ▼
This version uses fixed UTC offsets for simplicity. For most planning purposes that is fine — the seasonal shift is one hour and you can mentally compensate. If you need DST-accurate scheduling for a meeting weeks away, double-check the dates against tools like timeanddate.com that track political DST changes.
Can I compare more than two cities? ▼
Yes. The grid supports any number of cities. As you add more locations, the overlap window naturally shrinks — common windows for a London/New York/Sydney triangle are very narrow (typically 1-2 hours), while two-city pairs have much larger overlaps.
Is any scheduling data stored? ▼
No. The calculator runs entirely client-side. Your selected cities and any meeting plans are not transmitted anywhere — they exist only in your browser session and are forgotten when you close the tab.
What is the largest practical timezone gap? ▼
Sydney to Los Angeles is the classic challenging case (UTC+10/+11 vs UTC-7/-8 = 17-19 hour gap). The only standard work-day overlap is roughly 14:00–17:00 in LA matching 09:00–12:00 the next morning in Sydney. For cross-Pacific teams, asynchronous communication is usually the better default.
How do I find a "fair" meeting time across continents? ▼
A fair meeting rotates which team has to take an off-hours call. For an LA/London/Bangalore split, week 1 might be 7am LA / 3pm London / 8:30pm Bangalore (off-hours for India), week 2 might be 6am LA / 2pm London / 7:30pm Bangalore (still India's evening), and week 3 you might shift to favor LA/Bangalore at the cost of London. The grid helps you see all options at once.
What about teams with strict working hours? ▼
If everyone strictly enforces 9-5 local hours, multi-continent meetings often have zero overlap and require recorded async updates instead. This tool helps surface that reality early so teams can plan their collaboration model accordingly — synchronous calls require flexibility from at least one party.